The Influence of Cropping Systems on Photosynthesis, Yield, and Grain Quality of Selected Winter Triticale Cultivars

Abstract

Soil serves as the fundamental foundation for agricultural production; however, inappropriate utilization of soil in conventional cropping systems (CONV) coupled with agricultural practices focused on maximizing profit through the attainment of high-quality grain yield contributes to its degradation. An alternative to the CONV is the integrated cropping system (INTEG), which is based on sustainable plant cultivation by reducing the use of chemical pesticides and fertilizers. An interesting two-factor field experiment with winter triticale (×Triticosecale Wittm.) was conducted in 2019–2022 in south-eastern Poland. The experimental factors in this study included three winter triticale cultivars, namely Avokado, Medalion, Rotondo, and SU Liborius, and two cropping systems, CONV and INTEG. It was found that the use of the CONV brought out higher grain yield with higher protein and lower fat content. The cultivation of triticale grain under the CONV resulted in a higher thousand-grain weight (TGW), improved grain uniformity, and higher test weight values compared to INTEG. Additionally, the use of the CONV system resulted in improved values of physiological parameters (chlorophyll content and fluorescence and gas exchange), and that was caused by improved photosynthetic efficiency of triticale plants as a result of increased doses of mineral fertilizers, despite being cultivated in the INTEG; cv. SU Liborius achieved better values of yield parameters among the tested triticale cultivars grown in the CONV. Therefore, the selection of a suitable, efficient cultivar allows its growth under lower fertilization conditions and produces high grain yields of good quality. This knowledge can be valuable to farmers, as it would facilitate the selection of a triticale cultivar with the appropriate genetic profile for cultivation under specific agronomic conditions. Eventually, it would allow for the propagation of sustainable agricultural practices and contribute to enhancing soil biodiversity while maintaining the cost-effectiveness of agricultural production.

1. Introduction

Triticale (×Triticosecale Wittmack) is a human-made crop created by crossing rye (male parent) (Secale cereale L.) and wheat (female parent) (Triticum durum L. or Triticum aestivum L.) in 1875. The idea behind the development of triticale was to produce a species that combines the yield potential and grain quality of wheat with the disease resistance and environmental tolerance of rye [1,2,3]. Triticale has a high tolerance for growth in weaker soils, including acidified ones, and can be grown in poorer soils than wheat and slightly better than rye [4]. Triticale is also highly adaptable to local agroecological conditions, which contributes to obtaining a stable grain yield [5]. This species is characterized by high yield potential, good grain quality for forage use, and resistance to biotic and abiotic stresses [6,7]. The world cultivation area of triticale has been constantly growing and presently amounts to 3.8 million hectares. Poland is the main producer of this grain in the world. In 2021, triticale production in Poland amounted to 5.3 million tonnes [8]. Triticale is a valuable animal feed due to its nutritional properties, and, for this reason, presently, it is most often used for animal feeding (mainly poultry, pigs, and ruminants) [2]. Triticale grain is rich in starch and cellulose and, therefore, can be used in the energy industry for the production of biofuels [9,10] and straw and be used directly for heating [11]. In recent years, the cultivation of triticale for consumption purposes has been gaining in popularity [12]. Triticale grain can also be exploited in the baking industry due to its nutritional properties, where grain products are a valuable source of phenolic acids [13,14,15]. However, it is necessary to add that the factors limiting such use of triticale are high amylolytic activity and low gluten content, which adversely affect the bread-baking process [16,17]. The quantity and quality of grain yield are influenced by several factors, i.e., cultivar, agrotechnical practices, climatic and soil conditions, fertilization, and practices carried out in the case of the occurrence of agrophages [5,12,16].

The conventional cropping system (CONV) is a system of intensive crop cultivation based on the use of a large number of inputs, such as fertilizers and crop protection products [18]. The nitrogen (N) contained in fertilizers is a key ingredient that allows to achieve high yields of crop and promotes greater protein accumulation in grain. The availability of N is more important during growth, especially during the grain-filling period. As a result, it is important to apply an adequate dose of N while maintaining high yields and grain protein content. For intensive crop production, if we are to achieve a sustainable cropping system, the level of N fertilization and the time of its application are important, especially for high productivity and good-quality yields [19]. Implicitly, because of the result in increasing the intensity of the product, a negative impact of this cultivation system on the environment has been observed, which is manifested in its degradation, loss of biodiversity, and pollution of soil, water, and air [20,21].

A response to the growing consumer interest in sustainable food production, an alternative to the CONV, which skillfully combines agrotechnical treatments with reduced use of industrial inputs, is the integrated cropping system (INTEG). The usage of INTEG leads to an increase in the efficiency of inputs while minimalizing the negative impact on the natural environment and agriculture. While applying INTEG, it is crucial to reduce to the minimum necessary use of chemical pesticides and to precisely determine the dosage of mineral fertilizers, and it is derivative of the nutrient abundance of the soil and an assessment of the nutritional status of the plants. The system skillfully combines the use of chemical inputs (fertilizers and pesticides) with the application of methods used in organic farming (such as the use of Fabaceae plants as a forecrop). This system thus integrates the advantages of CONV and organic farming [22,23,24]. The issue of sustainable use of high inputs in agriculture is of great significance both economically and environmentally. Simultaneously, the impact of cropping systems on the environment, the nitrate content of water resources, and atmospheric emissions are important [25]. The INTEG, the key of which is an attempt to reconcile seemingly contradictory economic (the assumption of high farming efficiency), environmental, and social goals, represents one of the concepts of sustainable agricultural development [26]. In order to reduce the negative impact of excessive N fertilization on the environment and ensure food production at an appropriate level, it is necessary to improve the N use efficiency of modern cultivars. Therefore, in the cultivation of triticale, it is important to choose cultivars with an appropriate degree of N use efficiency. Thus, the grain yield of triticale depends on the level of N fertilization, which is related to the breeding of cultivars with the appropriate morphological structure of the roots and physiological pathways [27].

Considering the need to reduce the harmful effects of agricultural intensification on the environment, it is crucial to assess the yield of triticale under different cropping systems. Therefore, the aim of this research is to compare the impact of cropping systems on the course of physiological processes, yield, and grain quality traits of four selected winter triticale cultivars. The research hypothesis is that various triticale cultivars would react differently to the cropping systems commonly used. This would allow for the selection of the most productive cultivar, which can be grown in lower-intensity systems with less harmful environmental impacts.

2. Materials and Methods

2.1. Field Experiment Design

The field experiment with winter triticale was carried out at the Advisory Center in Boguchwała (49°59′ N, 21°56′ E) in south-eastern Poland in three growing seasons: 2019/2020, 2020/2021, and 2021/2022. The two-factor experiment has been conducted in triplicate using the randomized block method. The area of each experimental plot to be harvested amounted to 15 m². Four cultivars of winter triticale (×Triticosecale Wittm. ex A. Camus) have been selected for the experiment: Avokado and Rotondo (breeder DANKO HH Sp. z o. o.), Medalion (breeder Strzelce HR Sp. z o. o.) and SU Liborius (breeder Saaten-Union). Triticale has been grown in two cropping systems, CONV and INTEG, which have differed in the application of mineral fertilizer doses and the intensity of crop protection products. The forecrop for triticale in the CONV is winter wheat, while in the INTEG, it is broad bean. In the experiment, a stem shortening treatment was applied with Moddus 25 EC (trinexapac-ethyl, 0.2 l·ha⁻¹) twice in the CONV and once in INTEG. N fertilization in the CONV has been applied before sowing and after the start of vegetation (ammonium nitrate, 60%) and during the growing season (urea, 46%) (

Table 1. Consumption of fertilizers and pesticides in the winter triticale cropping systems.

Specification	Cropping Systems
	Conventional (CONV)	Integrated (INTEG)
Fertilization (kg·ha−1)
Nitrogen (N)	160 (4 applications: 20—presowing; 60—the start of vegetation; 50—BBCH 32–33; 30—BBCH 54–56)	90 (3 applications: 40—start of vegetation; 30—BBCH 32–33; 20—BBCH 54–56)
Phosphorus (P)	90	50
Potassium (K)	120	70
Pesticides
Herbicides	Expert Met 56 WG (metribuzin+ flufenacet) 0.35 l·ha−1 (BBCH 11–13)
Fungicides	Delaro 325 EC (prothioconazole+ trifloxystrobin) 1.0 l·ha−1 (BBCH 32–33); Bukat 500 SC (tebuconazole) 0.5 l·ha−1 (BBCH 54–56)	-
Insecticides	Karate Zeon 100 CS (lambda-cyhalothrin) 0.35 l·ha−1 (BBCH 54–56)

). In the CONV and INTEG systems, a one-time fertilization with phosphorus (superphosphate, 46%) and potassium (potassium salt, 60%) was applied. Additional treatment in the CONV has been foliar fertilization applied twice with Basfoliar 36 Extra (2.0 and 3.0 l·ha⁻¹). After harvesting the forecrop, the straw was crushed, and a stubble cultivator was used (depth 12–14 cm), followed by sowing plowing (depth 18–22 cm), and a cultivation aggregate was used before sowing. In both the CONV and INTEG systems, triticale was sown in the first week of October in the amount of 350 seeds·m².

2.2. Physiological Measurements

Measurements of physiological parameters were carried out in situ in the morning in the earing phase (55 BBCH) [28]. Measurements were made on fully expanded, randomly selected leaves in the central part of the leaf blade. The following measurements were taken:

−

Relative Chlorophyll Content (CCI unit) was measured using a Chlorophyll Content Meter CCM-200plus (Opti-Sciences, Hudson, NH, USA). These measurements were taken on 20 randomly selected leaves in each plot;

−

Chlorophyll Fluorescence measurements were taken using a hand-held chlorophyll fluorescence meter (Pocket PEA, Hansatech Instruments, King’s Lynn, Norfolk, UK). During the measurements, the following parameters were analyzed: maximum efficiency of PSII (Fv/Fm), quantum yield of the primary photochemistry (Fv/F0), and performance index (PI). Triticale leaves were adapted to darkness using light-withholding clips for 30 min. Measurements were taken on 4 randomly selected leaves in each plot [29];

−

Gas exchange was carried out using the Portable Photosynthesis Measurement System LCpro-SD (ADC BioScientific Ltd., Hoddesdon, UK). The parameters analyzed were photosynthetic rate (PN, mmol (CO₂)∙m⁻² s⁻¹), stomatal conductance (gs, mmol H₂O m⁻² s⁻¹), transpiration rate (E, mmol m⁻² s⁻¹), and intracellular CO₂ concentration (Ci, mol CO₂ m⁻² s⁻¹). The flag leaf was placed in the assimilation chamber, and after about 2 min, the gas exchange parameters were recorded in a data logger. The light intensity was 1500 mol m⁻² s⁻¹, and the temperature in the leaf chamber was 22 °C. Gas exchange measurements were carried out on 4 randomly selected plants in each plot.

2.3. Grain Yield

Triticale was harvested from the third week of July to the first week of August at the stage of full grain maturity (BBCH 89–92). Grain yield per plot was calculated per hectare, taking into account 15% moisture content.

2.4. Grain Quality Parameters

Test weight, referred to as mass per hectolitre, was determined using a density meter equipped with a 1000 mL cylinder [30], thousand-grain weight (TGW) at 15% moisture content using a grain counter (Sadkiewicz Instruments, Bydgoszcz, Poland) [31]. The grain uniformity is the ratio of the amount of grain remaining on sieves with specific longitudinal mesh sizes to the total weight of sifted grain. This indicator has been determined using [32] Vogel sieves on the SŻK Sadkiewicz mechanical sorter. A weighed sample of grain (100 g) was sieved through 6 drawer sieves with different mesh sizes (2.8, 2.5, and 2.2 mm) over a period of 3 min. The percentage of the summed results from the top two sieves has been indicated.

The crude protein content of triticale grain was determined by the Kjeldahl method [33], crude fat by the Soxhlet method, and crude fiber by the Henneberg-Stohman method as modified by Pruszynski), while crude ash was determined by combusting the material at 600° [34].

2.5. Environmental Conditions

2.5.1. Soil Conditions

The experiment was established on Haplic Cambisol (Cmha) soil developed from silty clay [35] (

Table 2. Soil basic fertility before setting up the experiment (0–35 cm).

Year	pH in 1 mol·dm−3 KCl	Soil Organic Carbon (SOC)	Nmin	Phosphorus (P)	Potassium (K)	Magnesium (Mg)
		%	kg·ha−1	mg·kg−1 Soil
2019/2020	5.40	1.12	57.3	102	140	136
2020/2021	5.30	1.19	59.4	135	160	152
2021/2022	5.45	1.31	60.1	125	173	147

SOC (Tiurin’s method) [36]; N_min (in 0.01 CaCl₂ solution) [37]; P, K (Egner-Riehm’s method) [38]; Mg (Schachtschabel’s method) [39].

). The soil pH was slightly acidic and had a very high phosphorus content. The potassium content was very high in the 2021/2022 season, while it was average in the other years of the study. The amount of N min and soil organic carbon (SOC) has been described as low.

2.5.2. Weather Conditions

Weather conditions during the course of the experiment were variable throughout the study years (Figure 1). In the 2019/2020 season, very high rainfall amounts were found in June, while in the 2020/2021 season, high rainfall amounts were found in August. Compared to long-term precipitation, these values were 94.5 and 67.7% higher, respectively. The warmest season among the study years analyzed was the 2019/2020 season, in which the average air temperature was 1.9 °C higher than the long-term temperature. In the other seasons of the study, air temperatures were 0.9 °C higher than the long-term temperature.

Analysis of hydrothermal conditions according to Skowera et al. [40] showed that during the spring–summer growing season in 2020, hydrothermal conditions were described as humid and very humid in May and June, while extremely dry and dry in April and July (Figure 2). In 2021, compared to the other years of the study, hydrothermal conditions in May through August were the most favorable for the cultivation of triticale. In 2022, hydrothermal conditions were described as very dry (July) and extremely dry (May, June, August).

2.6. Statistical Analysis

Statistical analysis of the obtained results was performed using TIBCO Statistica 13.3.0 (TIBCO Software Inc., Palo Alto, CA, USA) program. The Shapiro–Wilk test was used to check the normality of the distribution. A three-factor analysis of variance (ANOVA) was conducted to determine the effect of year, cropping system, and cultivar on the physiological parameters, yield, and grain quality parameters of triticale. Tukey’s post hoc test (p ≤ 0.05) was used to determine the significance of differences between the mean values of the studied parameters.

3. Results

3.1. Physiological Parameters

3.1.1. Chlorophyll Content and Chlorophyll Fluorescence

Both the chlorophyll content and the value of selected chlorophyll fluorescence parameters depended significantly on the experimental factors (

Table 3. Chlorophyll content and selected chlorophyll fluorescence indicators in triticale leaf in ear emergence (BBCH 55) depending on cropping system, cultivars, and year of experiment.

Factor		Chlorophyll Content (CCI)	Chlorophyll Fluorescence
Cropping System (CS)	Cultivar (C)		Fv/Fm	Fv/F0	PI
CONV		41.5 ± 5.7 b	0.821 ± 0.020 b	4.65 ± 0.60 b	12.37 ± 3.18 b
INTEG		35.9 ± 6.8 a	0.795 ± 0.031 a	3.96 ± 0.64 a	9.11 ± 3.76 a
Avokado		34.8 ± 6.7 a	0.786 ± 0.036 a	3.77 ± 0.73 a	7.63 ± 3.42 a
Medalion		38.5 ± 6.4 b	0.811 ± 0.021 b	4.33 ± 0.58 b	10.84 ± 2.99 b
Rotondo		38.2 ± 6.2 b	0.809 ± 0.027 b	4.33 ± 0.67 b	10.62 ± 3.71 b
SU Liborius		43.4 ± 5.7 c	0.826 ± 0.015 c	4.79 ± 0.50 c	13.87 ± 2.59 c
Year (Y)	2019/2020	32.4 ± 5.8 a	0.782 ± 0.032 a	3.67 ± 0.64 a	8.11 ± 3.35 a
	2020/2021	44.7 ± 4.0 c	0.825 ± 0.016 c	4.76 ± 0.43 c	12.04 ± 4.14 b
	2021/2022	39.0 ± 3.9 b	0.817 ± 0.015 b	4.49 ± 0.53 b	12.08 ± 2.50 b
Mean		38.7 ± 6.8	0.808 ± 0.029	4.31 ± 0.71	10.74 ± 3.82
CS		F = 96.99 p < 0.0001	F = 222.1 p < 0.0001	F = 339.97 p < 0.0001	F = 38.364 p < 0.0001
C		F = 38.09 p < 0.0001	F = 88.2 p < 0.0001	F = 120.29 p < 0.0001	F = 23.384 p < 0.0001
Y		F = 154.81 p < 0.0001	F = 220.5 p < 0.0001	F = 299.22 p < 0.0001	F = 25.015 p < 0.0001
CS × C		ns	F = 5.6 p < 0.001	ns	ns
CS × Y		ns	F = 8.2 p < 0.001	F = 5.45 p < 0.05	F = 4.208 p < 0.05
C × Y		ns	F = 8.6 p < 0.0001	F = 3.40 p < 0.05	ns
CS × C × Y		ns	ns	ns	ns

The data shown are mean ± standard deviation (SD). Different letters within a column indicate significant differences according to Tukey’s test at p < 0.05; ns—non-significant; Fv/Fm—maximum efficiency of PSII; Fv/F0—quantum yield of the primary photochemistry; PI—performance index.

). As far as the tested parameters are concerned, a significant increase in their value has been found as a result of cultivation under the CONV. Among the tested triticale cultivars, the cv. Avokado achieved the lowest values, while SU Liborius showed the highest values of the analyzed parameters. Triticale cultivation has shown a differential effect on fluorescence values and leaf chlorophyll content in each year of the study. The conditions for the 2020/2021 season resulted in the most favorable chlorophyll content and Fv/Fm and Fv/F0 parameter values, while the PI values obtained for the 2020/2021 and 2021/2022 seasons did not differ.

A significant interaction between experimental factors was shown for both chlorophyll content and Fv/Fm, Fv/F0, and PI values (Figure 3a–d). It has been indicated that the cv. SU Liborius grown under INTEG achieved similar chlorophyll contents with the cvs. Avokado, Medalion, and Rotondo grown under a CONV. In the cases of Fv/Fm and Fv/F0, the cv. SU Liborius cultivated under the INTEG had values of these parameters at the level of the cvs. Medalion and Rotondo cultivated under the CONV. There were no differences in PI values between all triticale cultivars grown under the CONV and the cv. SU Liborius grown under the INTEG.

3.1.2. Gas Exchange Parameters

Cultivation of triticale under the CONV, as in the case of chlorophyll content and fluorescence, influenced an increase in gas exchange values, Pn and Gs, while causing a decrease in Ci (

Table 4. Selected gas exchange indicators in triticale leaf in ear emergence (BBCH 55) depending on cropping system, cultivars, and year of experiment.

Factor		Gas Exchange
Cropping System (CS)	Cultivar (C)	Pn (mmol(CO2)∙m−2∙s−1)	Gs (mol(H2O)∙m−2∙s−1)	E (mmol(H2O)∙m−2∙s−1)	Ci (μmol(CO2)∙ mol−1)
CONV		21.89 ± 1.29 b	0.829 ± 0.340 b	3.86 ± 0.72 a	279.5 ± 23.1 a
INTEG		19.88 ± 1.16 a	0.703 ± 0.259 a	3.78 ± 0.84 a	283.4 ± 25.9 b
Avokado		19.44 ± 1.14 a	0.610 ± 0.209 a	3.64 ± 0.44 a	279.2 ± 30.4 a
Medalion		20.81 ± 1.28 b	0.798 ± 0.345 b	3.90 ± 0.92 a	283.0 ± 23.7 a
Rotondo		20.88 ± 1.19 b	0.766 ± 0.264 b	3.83 ± 0.87 a	282.5 ± 22.4 a
SU Liborius		22.42 ± 1.22 c	0.890 ± 0.351 b	3.89 ± 0.84 a	281.0 ± 23.0 a
Year (Y)	2019/2020	20.70 ± 1.50 a	0.697 ± 0.100 a	2.97 ± 0.51 a	309.6 ± 5.9 c
	2020/2021	21.11 ± 1.76 a	1.097 ± 0.100 c	4.64 ± 0.17 c	254.6 ± 13.1 a
	2021/2022	20.84 ± 1.55 a	0.504 ± 0.131 b	3.83 ± 0.32 b	280.1 ± 5.6 b
Mean		20.89 ± 1.58	0.766 ± 0.306	3.82 ± 0.78	281.4 ± 24.3
CS		F = 131.83 p < 0.0001	F = 11.031 p < 0.001	ns	ns
C		F = 48.56 p < 0.0001	F = 9.452 p < 0.001	ns	ns
Y		ns	F = 85.007 p < 0.0001	F = 101.419 p < 0.0001	F = 184.69 p < 0.0001
CS × C		ns	ns	ns	ns
CS × Y		ns	ns	ns	ns
C × Y		ns	ns	F = 2.658 p < 0.05	ns
CS × C × Y		ns	ns	ns	F = 2.57 p < 0.05

The data shown are mean ± standard deviation (SD). Different letters within a column indicate significant differences according to Tukey’s test at p < 0.05; ns—non-significant; PN—photosynthetic rate; Gs—stomatal conductance; E—transpiration rate; Ci—intracellular CO₂ concentration.

). Only in the case of Pn and Gs has the cultivar factor significantly affected the differentiation of gas exchange parameter values. The lowest Pn value has been found in cv. Avokado, while the highest has been found in cv. SU Liborius. In the case of Gs, the lowest value compared to the other cultivars has been obtained in cv. Avokado. Compared to the cvs. Medalion, Rotondo, and SU Liborius, this value was lower by 30.8, 25.6, and 45.9%, respectively. The years of the study did not differentiate the value of Pn. In the case of Gs and E, the lowest value of these parameters was found in the 2019/2020 season, while the highest was found in 2020/2021. Triticale cultivation in the 2019/2020 season resulted in the highest Ci value, while in the 2020/2021 season, it was the lowest.

A significant interaction between the experimental factors for gas exchange parameters has also been indicated for Pn and Gs (Figure 4). Cultivation of the cv. SU Liborius under the INTEG has resulted in similar Pn values as for the cvs. Avokado, Rotondo, and Medalion grown under the CONV. In the case of Gs, there have been no differences between the cvs. Medalion, Rotondo, and SU Liborius cultivated under the INTEG and the cvs. Medalion and Rotondo grown under the CONV. Cv. Avokado, while using both CONV and INTEG systems cultivation, achieved lower Gs value than the cv. SU Liborius grown under the INTEG by 29.5 and 41.5%, respectively.

3.2. Grain Yield, Yield Attributes, and Grain Quality Parameters

The average grain yield of triticale in the experiment conducted amounted to 8.06 t·ha⁻¹ (Figure 5). The factors of the experiment significantly affected the yield obtained. Cultivation under the CONV has resulted in a significant increase in yield by 16.2% compared to the INTEG. The study has demonstrated that cv. Avokado cultivated under the INTEG has yielded the lowest among the other cultivars. Despite the cultivation of these triticale cultivars under the CONV, grain yield was not significantly different from that obtained with the cvs. Medalion and Rotondo grown under the INTEG (Figure 6). The highest yield has been found in the cv. SU Liborius, regardless of the cultivation system used. The values have amounted to 9.05 t·ha⁻¹ under the INTEG and 10.15 t·ha⁻¹ under the CONV. Cultivation of the cv. SU Liborius in the INTEG has resulted in higher yield values than the other cultivars grown under the CONV. The years of the study also affected the obtained grain yield. The 2020/2021 season had the most favorable weather conditions for the growth and development of triticale plants, which resulted in receiving the highest yield compared to the 2019/2020 and 2022/2022 seasons by 68.3 and 18.4%, respectively.

Triticale cultivation under the CONV resulted in an increase in the number of ears, the number of grains per ear, and TGW compared to the INTEG system by 13.5, 14.7, and 11.5%, respectively (

Table 5. Yield attributes of triticale depend on the cropping system, cultivars, and year of the experiment.

Factor		Number of Ears (pcs.·m−2)	Number of Grains per Ear (pcs.)	Thousand-Grain Weight (TGW) (g)
Cropping System (CS)	Cultivar (C)
CONV		589.6 ± 59.0 b	56.2 ± 9.3 b	47.6 ± 3.3 b
INTEG		519.3 ± 62.0 a	49.0 ± 8.3 a	42.7 ± 3.8 a
Avokado		558.4 ± 80.6 a	48.6 ± 6.9 a	42.8 ± 4.9 a
Medalion		560.7 ± 52.3 a	49.1 ± 5.5 a	44.5 ± 2.3 a
Rotondo		554.5 ± 75.2 a	55.2 ± 11.9 b	43.6 ± 3.3 a
SU Liborius		544.4 ± 75.1 a	57.3 ± 10.2 b	49.6 ± 2.9 b
CONV	Avokado	584.9 ± 78.5 c	51.3 ± 6.9 bc	46.2 ± 3.4 bc
	Medalion	584.7 ± 31.8 c	50.5 ± 5.1 abc	46.1 ± 1.4 bc
	Rotondo	597.8 ± 68.8 c	61.4 ± 8.3 d	46.2 ± 2.2 bc
	SU Liborius	591.0 ± 62.8 c	61.5 ± 11.2 d	51.8 ± 1.6 d
INTEG	Avokado	531.9 ± 80.3 b	46.0 ± 6.3 a	39.4 ± 3.7 a
	Medalion	536.6 ± 60.2 b	47.6 ± 5.9 ab	43.0 ± 2.0 ab
	Rotondo	511.1 ± 56.7 ab	49.0 ± 12.3 abc	41.1 ± 1.7 a
	SU Liborius	497.7 ± 57.0 a	53.2 ± 7.8 c	47.3 ± 1.9 c
Year (Y)	2019/2020	500.0 ± 43.7 a	44.8 ± 6.1 a	45.9 ± 3.8 a
	2020/2021	624.0 ± 40.6 c	59.7 ± 9.1 c	44.7 ± 3.3 a
	2021/2022	539.4 ± 55.4 b	53.1 ± 6.6 b	44.8 ± 5.6 a
Mean		554.5 ± 69.6	52.6±	45.1 ± 4.3
CS		F = 266.80 p < 0.0001	F = 90.90 p < 0.0001	F = 74.35 p < 0.0001
C		ns	F = 33.43 p < 0.0001	F = 28.96 p < 0.0001
Y		F = 288.85 p < 0.0001	F = 130.28 p < 0.0001	ns
CS × C		F = 7.19 p < 0.05	F = 7.53 p < 0.05	ns
CS × Y		F = 6.00 p < 0.05	ns	F = 5.98 p < 0.05
C × Y		F = 13.66 p < 0.0001	F = 16.53 p < 0.0001	ns
CS × C × Y		F = 5.47 p < 0.05	F = 2.71 p < 0.05	F = 2.75 p < 0.05

The data shown are mean ± standard deviation (SD). Different letters within a column indicate significant differences according to Tukey’s test at p < 0.05; ns—non-significant.

). The cultivar factor influenced the formation of the values of the studied parameters only in the case of the number of grains per ear and TGW. Plants of all tested triticale cultivars cultivated under the CONV developed the highest number of ears, while the SU Liborius and Rotondo cvs. cultivated under the INTEG developed the lowest ones. As for the number of grains per ear, the highest number has been observed in the cvs. Rotondo and SU Liborius cultivated under the CONV. Cv. SU Liborius grown under the INTEG had a comparable number of grains per ear to cvs. Avokado and Medalion grown under the CONV. A similar relationship has been reported for TGW. Cv. SU Liborius grown under the INTEG showed no differences in the value of this parameter with cvs Avokado, Medalion, and Rotondo grown under the CONV. Cultivation of triticale in the 2020/2021 season resulted in the highest values of the number of ears and number of grains per ear, while in the 2019/2020 season, the lowest numbers had the lowest values. In the case of TGW, the effect of the years of testing on the differentiation of its values has not been shown.

The cultivation of triticale under the CONV has resulted in a significant increase in test weight (by 1.9%) and grain uniformity (by 3.8%) compared to the INTEG (

Table 6. Test weight and grain uniformity depending on cropping system, cultivars, and year of experiment.

Factor		Test Weight (kg·hl−1)	Grain Uniformity (%)
Cropping System (CS)	Cultivar (C)
CONV		68.2 ± 4.7 b	87.0 ± 11.1 b
INTEG		66.9 ± 4.9 a	83.8 ± 11.4 a
Avokado		66.6 ± 5.1 ab	81.6 ± 12.1 a
Medalion		66.2 ± 4.5 a	83.4 ± 11.5 a
Rotondo		70.3 ± 4.8 c	87.8 ± 11.8 b
SU Liborius		67.1 ± 4.0 b	88.9 ± 9.0 b
CONV	Avokado	67.2 ± 5.3 bc	84.2 ± 13.6 bcd
	Medalion	66.7 ± 5.0 abc	85.1 ± 11.8 cde
	Rotondo	71.0 ± 4.8 d	89.0 ± 11.6 de
	SU Liborius	68.0 ± 3.7 c	89.8 ± 8.8 e
INTEG	Avokado	66.1 ± 5.4 ab	79.0 ± 10.9 a
	Medalion	65.7 ± 4.4 a	81.7 ± 12.2 ab
	Rotondo	69.6 ± 5.2 d	86.6 ± 13.0 cde
	SU Liborius	66.1 ± 4.5 ab	88.1 ± 10.0 cde
2019/2020		64.1 ± 2.2 a	71.3 ± 4.8 a
2020/2021		73.6 ± 2.1 c	94.5 ± 2.0 c
2021/2022		65.0 ± 2.0 b	90.5 ± 6.5 b
Mean		67.6 ± 4.8	85.4 ± 11.2
CS		F = 40.8 p < 0.0001	F = 24.48 p < 0.0001
C		F = 79.9 p < 0.0001	F = 29.93 p < 0.0001
Y		F = 830.5 p < 0.0001	F = 496.73 p < 0.0001
CS × C		ns	ns
CS × Y		ns	F = 5.01 p < 0.05
C × Y		F = 10.4 p < 0.0001	F = 5.74 p < 0.001
CS × C × Y		ns	F = 4.2 p < 0.05

The data shown are mean ± standard deviation (SD). Different letters within a column indicate significant differences according to Tukey’s test at p < 0.05; ns—non-significant.

). Cv. Rotondo had the highest value of test weight, while cv. SU Liborius had the highest value of grain uniformity compared to the other cultivars. Regardless of the cropping system, the cultivation of cv. Rotondo resulted in the highest test weight value. As far as the grain uniformity is concerned, the highest values were obtained for the cvs. Medalion, Rotondo, and SU Liborius grown under the CONV and the cvs. Rotondo and SU Liborius grown under the INTEG. The years of the study also have significantly affected the value of the parameters studied. The cultivation of triticale in the 2020/2021 season resulted in the highest values of test weight and grain uniformity, while the 2019/2020 season had the lowest.

The cropping systems have affected the protein and fat contents, whereas the fiber and ash contents of triticale grain have not been affected (

Table 7. The content of organic components and ash in triticale grain depends on the cropping system, cultivars, and year of the experiment.

Factor		Crude Protein	Crude Fat	Crude Fibre	Crude Ash
Cropping System (CS)	Cultivar (C)	g·kg−1
CONV		132.6 ± 6.2 b	17.0 ± 2.7 a	22.8 ± 4.5 a	21.3 ± 7.4 a
INTEG		128.7 ± 9.8 a	18.7 ± 2.6 b	24.2 ± 4.5 a	19.9 ± 2.4 a
Avokado		128.8 ± 7.8 a	17.2 ± 2.5 a	25.3 ± 4.5 b	19.5 ± 1.9 a
Medalion		133.1 ± 8.1 a	18.6 ± 3.9 b	25.4 ± 4.7 b	23.2 ± 10.1 a
Rotondo		129.3 ± 9.5 a	17.6 ± 2.0 ab	23.4 ± 2.9 b	20.0 ± 2.3 a
SU Liborius		131.4 ± 8.2 a	17.9 ± 2.3 ab	19.9 ± 3.7 a	19.6 ± 2.6 a
CONV	Avokado	131.8 ± 4.8 ab	17.5 ± 2.6 ab	24.4 ± 6.1 abc	19.5 ± 2.2 a
	Medalion	135.5 ± 8.4 b	17.3 ± 4.3 ab	24.5 ± 4.0 bc	26.4 ± 13.9 a
	Rotondo	131.6 ± 6.1 ab	16.6 ± 1.3 a	23.3 ± 3.0 abc	20.1 ± 2.2 a
	SU Liborius	131.6 ± 5.8 ab	16.8 ± 2.6 ab	19.1 ± 2.7 a	19.2 ± 2.2 a
INTEG	Avokado	125.8 ± 9.5 a	17.0 ± 2.6 ab	26.2 ± 2.4 c	19.4 ± 1.7 a
	Medalion	130.7 ± 7.7 ab	20.0 ± 3.3 c	26.2 ± 5.6 c	20.0 ± 2.5 a
	Rotondo	127.1 ± 12.3 a	18.6 ± 2.2 abc	23.5 ± 3.1 abc	20.0 ± 2.7 a
	SU Liborius	131.2 ± 10.7 ab	19.1 ± 1.5 bc	20.8 ± 4.6 ab	20.0 ± 3.1 a
2019/2020		139.1 ± 3.8 c	16.4 ± 1.7 a	23.1 ± 4.3 a	24.7 ± 8.0 b
2020/2021		129.1 ± 6.0 b	20.7 ± 1.9 b	25.7 ± 5.1 b	18.9 ± 1.2 a
2021/2022		123.8 ± 6.2 a	16.5 ± 2.1 a	21.6 ± 3.1 a	18.1 ± 1.0 a
Mean		130.7 ± 8.3	17.9 ± 2.8	23.5 ± 4.5	20.6 ± 5.5
CS		F = 12.26 p < 0.05	F = 20.534 p < 0.001	ns	ns
C		F = 3.17 p < 0.05	ns	F = 10.050 p < 0.001	ns
Y		F = 64.94 p < 0.0001	F = 62.992 p < 0.0001	F = 8.879 p < 0.05	F = 11.253 p < 0.001
CS × C		ns	F = 4.210 p < 0.05	ns	ns
CS × Y		F = 5.91 p < 0.05	ns	ns	ns
C × Y		F = 3.30 p < 0.05	F = 4.32 p < 0.05	F = 6.021 p < 0.001	ns
CS × C × Y		ns	ns	ns	ns

The data shown are mean ± standard deviation (SD). Different letters within a column indicate significant differences according to Tukey’s test at p < 0.05; ns—non-significant.

). The use of the CONV has resulted in higher protein contents by 3.0% and lower fat contents by 10.0% than in the INTEG. There were no significant differences in grain protein content between the tested cultivars. It has been shown that the cv. Medalion grown under the CONV is characterized by a higher protein content in the grain than the cvs. Avokado (7.7%) and Rotondo (6.6%) grown under the INTEG. The fat content was higher in the cv. Medalion grew under the INTEG compared to the cv. Rotondo under the CONV by 20.5%. In the case of grain fiber content, the lowest values were found in the cv. SU Liborius (19.9 g·kg⁻¹). The ash content has not been determined by both experimental factors and the interaction between them. Years of study significantly affected protein, fat, fiber, and ash content. The 2019/2020 cropping season resulted in the highest protein and ash content, while the 2020/2021 season resulted in fat and fiber content.

4. Discussion

4.1. Physiological Parameters

The present study investigates the physiological status of triticale cultivars grown under CONV and INTEG systems.

Plant growth and its development are influenced by the course of photosynthesis, which depends on environmental factors and the nutritional status of plants [41]. In this study, chlorophyll content has been higher as a result of cultivation under the CONV in which a higher N rate was applied, as confirmed by the results of the study Janušauskaitė [42] and Jańczak-Pieniążek et al. [43]. The chlorophyll content is a parameter determined genetically and by weather factors, including precipitation. The experiment has shown cultivar differentiation in chlorophyll content and the effect of years of study, which has also been confirmed by other authors [43,44].

Chlorophyll fluorescence is considered by many authors as a fast, non-invasive, and effective measurement method that reflects the response of plants to environmental stress caused by, among others, unfavorable weather conditions [45]. This method seeks to estimate the functional state of the photosynthetic apparatus and performs measurements at different developmental stages of plants during the whole growing season [29,46]. Chlorophyll content and the parameters of chlorophyll fluorescence and gas exchange can be used as a selection criterion in breeding plant genotypes characterized by the most efficient photosynthetic apparatus, which may indicate their better adaptation to unfavorable environmental conditions [42,47]. The chlorophyll fluorescence measurement method is used to assess the effects of stress in plants before visual changes in leaves are observed [48]. The study indicates lower values of chlorophyll fluorescence parameters Fv/Fm and Fv/F0 in the 2019/2020 and 2021/2020 seasons, in which unfavorable weather conditions were found. Chlorophyll fluorescence parameters, especially Fv/Fm and PI, depend not only on the water deficit in the soil but also on leaf temperature. These parameters are able to reflect the effects of various stress factors and deficits on plant vigor and are intended to differentiate the tested crop cultivars as more or less resistant [49,50].

The study also has shown a favorable effect of using technologies with higher input intensity on Fv/Fm, Fv/F0, and PI parameters, the values of which were higher in relation to those obtained under the INTEG. N nutrition plays a decisive role in determining the process of plant photosynthesis in the agricultural environment and biomass accumulation [51]. The appropriate level of fertilization improves the photosynthetic efficiency of crop plants, while deficiency causes disturbances in the functioning of the photosynthetic apparatus and reduces the photochemical efficiency of PSII [52]. Janušauskaite i Feiziene [53], in their research on spring triticale, showed that chlorophyll fluorescence parameters in fertilized plants increase as a result of increasing mineral fertilizer doses. The nutritional status of triticale, as in other cereals, is closely related to the efficiency of photosynthesis since the inappropriate application of mineral fertilizers can result in the occurrence of stress in plants, consequently leading to a disruption of their growth and development. However, the use of fertilizers, despite the positive effect on the value of chlorophyll fluorescence parameters, can be a stress factor for plants during the application of fertilizers [53].

Measurements of gas exchange parameters provide information on the intensity of photosynthesis and control of stomatal mechanisms [54]. Many factors can affect the value of gas exchange parameters, including the age of the plant, leaf architecture, and also environmental factors such as air temperature, light, soil moisture, and nutritional status [55,56]. The conducted research showed only a statistically insignificant increasing tendency of Pn in the 2020/2021 season, in which the most favorable weather conditions for triticale cultivation were recorded.

A study by Hura et al. [47] has shown cultivar differentiation in the photosynthetic activity of triticale plants grown under optimal growth conditions. In the conducted study, there was also a significant influence of cultivars on the values of Pn and Gs parameters. The cv. Avokado has had the lowest Pn values, while the cvs. Medalion, Rotondo, and SU Liborius have shown higher Gs than the cv. Avokado. The functioning of the photosynthetic apparatus in various genotypes is different. Differences in photosynthetic activity can become the basis for selecting genotypes with the most efficient photosynthetic apparatus. Such information would provide important data on the potential of a given genotype and are important criteria for the selection of genotypes better adapted to unfavorable conditions [47].

4.2. Grain Yield, Yield Attributes, and Grain Quality Parameters

Grain yield is a quantitative trait controlled by numerous genes, and it is simultaneously the final result of both environmental factors on the plant and the activity of certain physiological and biochemical processes [57,58]. According to many authors, the yield of triticale can be strongly modified by the environment, weather, and agrotechnical conditions and rarely depends on a single factor [57,59,60,61].

The unfavorable weather conditions during the growing season of triticale can significantly contribute to a decrease in yield, and that fact confirms that the yield depends not only on agrotechnical conditions and the cultivar but also on the weather conditions occurring in each year of the study [57]. In their study, Rajičić et al. [60] indicated that triticale grain yield and quality tended to increase in study years characterized by higher sum and better distribution of precipitation at critical growth stages. The dependence of yield on the years of study has also been confirmed by Jaśkiewicz [61]. Similar relationships were shown in the conducted study, in which the highest grain yields of triticale were obtained in the 2020/2021 season, with the most favorable distribution of temperature and precipitation. The yield instability can be the result of temperature fluctuations, variable amounts of precipitation during the growing season, and poor soil moisture. One of the factors limiting much of the world’s crop production is drought, which, in combination with high temperatures, intensifies the negative impact of environmental stresses [7]. According to Lalević et al. [57] and Janušauskaite [19], the individual or mutual effect of abiotic stresses, including those related to unfavorable weather factors occurring at different growth stages of triticale, limits the potential of this species to achieve a maximal yield.

The yield obtained is also strongly influenced by TGW, which is determined by the morphological characteristics of the grains: their length, width, and surface area. These values have an impact on the density of grains at bulk determining milling and baking quality, seedling vigor, and resistance to osmotic stress [58]. According to Bielski et al. [59], weather conditions are particularly important for the formation of TGW since, during the period of filling the grain, the lack of moisture and high temperature decrease the value of this parameter. In the conducted study, the relationship of TGW to years of research has not been indicated.

The conducted study has found a significantly higher grain yield of 16.2% in the CONV compared to INTEG. The higher yield potential of triticale under the CONV may be due to the higher availability of N, which is among the basic and most important elements that have the biggest impact on the processes of vegetative growth of plants, photosynthetic capacity, and, consequently, yield. N fertilization also has a stimulating effect on the growth of the root system and its penetration into the soil [57].

The number of ears has been classified among the yield-shaping parameters [62]. In the experiment conducted, an increase in the N fertilization rate applied in the CONV has shown a significant effect on increasing the number of ears. Such a relationship has also been confirmed by a study conducted by Bielski et al. [63] in which, as the N dose increased, an increase in the number of ears per unit area was observed. Đekić et al. [5] and Bielski et al. [63] also report the effect of N fertilization on the TGW growth of triticale. These authors, as in the conducted research, have shown a significant effect of the years of study on the differentiation of spike density. The experiment has also shown a significant effect of the cultivar factor on TGW. Among the tested cultivars, cv. SU Liborius has had the highest value of this parameter. TGW is largely determined by the genome; thus, more variation is observed among genotypes than environmental factors [5], as shown in the conducted study. The results obtained in the conducted experiment indicate and confirm the opinion of the other authors that yield-forming parameters are genetically determined and modified by weather conditions and soil nutrient availability [60,63].

In addition to grain weight, size and shape also determine the test weight and grain uniformity, which are important indicators of grain quality and its technological suitability. These parameters determine the milling yield and protein content of the grain [64,65]. In the study performed by Đekić et al. [5], test weight increased as a result of N fertilization, which was confirmed in the conducted study. According to Bielski [59], while studies with triticale, in addition to N fertilization, grain yield, and TGW have also been influenced by fungicide protection, which has been applied in the CONV in the experiment performed. The aforementioned has confirmed that higher yields can be achieved with crop protection treatments, including fungicides.

Obtaining a sufficiently high yield of triticale grain of the expected quality requires, in addition to ensuring optimal growing conditions, the selection of a cropping system and the appropriate selection of a cultivar. The selection of a suitable, productive cultivar is essential since it allows for achieving a high degree of tolerance to unfavorable weather conditions and drought, especially at the stage of grain formation [60,66,67]. The selection of a cultivar with higher N use efficiency is important, particularly in the aspect of reducing the negative impact of excessive use of N fertilizers on the environment and ensuring sufficient food production for the world’s population [27,68]. In breeding triticale cultivars, it is also of high significance to improve them by increasing their productivity under limited water regimes [7].

Triticale grain has high nutritional value [16]. Previous studies showed that the nutritional properties of triticale are in intermediate positions between wheat and rye but are more similar to wheat [2,69]. The content of total protein, both in the grain of triticale and other cereals, is not only a cultivar trait but also depends on environmental factors and fertilization, and plant protection. In triticale grain, the crude protein content is within the range of 90 to 200 g kg⁻¹ d.m. The conducted study has shown an average protein content in grains of 130 g kg⁻¹ d.m. Triticale protein has a higher biological value compared to wheat protein, as it contains more lysine, which is a limiting amino acid [2,70]. As a result of cultivation under the CONV in the conducted study, higher protein content was obtained, which was also proven in the study of Knapowski et al. [71], who demonstrated the effect of fertilization on the yield and baking value of spring triticale. Also, in their study of triticale, Jaskiewicz and Szczepanek [72] showed that triticale grown under intensive technology, in which higher doses of mineral fertilizers and pesticides were used, tends to lead to the accumulation of more protein in the grain compared to INTEG. N fertilization is believed to promote the formation of protein aggregates. As reported by Langó et al. [69], triticale grain shows large cultivar differentiation in protein, fat, and fiber content. The nutritional value of different triticale genotypes indicates that they can also be used in food products, not only for feed applications.

5. Conclusions

Cultivation systems and years of study affect the physiological processes, yield, and grain quality of the winter triticale cultivars tested. It has been shown that the use of the CONV, in which a higher dose of N and crop protection products are applied, has had a positive effect in obtaining a higher grain yield. It has also brought effects in the form of higher protein content, lower fat content, higher TGW, grain uniformity, and test weight values. Triticale cultivation in the CONV also has exerted a stimulating effect on the course of physiological processes. The parameters of chlorophyll content and fluorescence, and gas exchange have been improved. Cv. SU Liborius has been characterized by the best values of yielding parameters among the tested triticale cultivars. Cultivation of this cultivar in the INTEG has resulted in similar values of the tested physiological indicators as the cvs. Medalion and Rotondo in the CONV system. The aforementioned have demonstrated the need to select productive cultivars that yield high utility values in systems with lower inputs, which, in turn, contributes to sustainable farming practices and protects the environment and soils from degradation.