Department of Water Sciences and Engineering, College of Agriculture and Natural Resources, Ardakan University, Ardakan, 89518- 95491, Iran.
Water, Energy and Environment Research Institute, P.O. Box 184, Ardakan, Iran.
Sci Rep. 2024 Oct 10;14(1):23665. doi: 10.1038/s41598-024-74849-9.
Drought is one of the abiotic stresses that can reduce crop yields. It has a major impact on crop yield reduction. For crops under stress, organic modifiers such as biochar can be useful. Guar (Cyamopsis tetragonoloba L.), an annual legume from the Fabaceae Family, is highly adaptable to arid and semi-arid regions, with many applications in various industries. Field experiments were carried out in a randomized complete block design with three replications using a split-split plots arrangement. The aim was to evaluate the influence of irrigation levels (Ir1 = 10, Ir2 = 14, and Ir3 = 17 days irrigation cycle) and biochar (B1 = 0, B2 = 5, and B3 = 10 tons ha) application on physiological traits [(chlorophyll a and b, chlorophyll index (SPAD), relative leaf water content (RWC), electrolyte leakage (EL), canopy temperature, leaf area, water use efficiency (WUE)], morphological parameters (length and diameter of the stem, pod length, fresh weight of root and plant, root length), yield components (seed yield, number of branch plant, number of clusters plant, pod plant, seed pod, seed plant, 1000-seed weight, and gum contents), and leaf nutrient uptake (Ca, Mg, P, Na, and K) of two commercial and local cultivars (cv1 = RGC-936 and cv2 = Saravan) of the guar plant. It was observed that the Ir3 irrigation treatment produced the highest seed yield (1921.8 kg ha) in terms of water stress. However, the maximum pod plant (75.5), seed plant (454.2), seed yield (1871.1 kg ha), leaf area (861.8 mm), SPAD (92.2), Mg (49.8 mg g), Na (43.3 mg g) and P (0.49 mg g) were observed in RGC-936. The results also revealed that biochar was more effective than cultivars in terms of morphological traits. While yield and yield components were affected by cultivar, irrigation at different levels also had a significant effect on functional traits, physiology, and morphology. The addition of biochar appeared to have a positive effect on water stress alleviation and guar growth and leaf nutrient uptake. According to Pearson's correlation analysis, plant weight and length, root weight and length, stem diameter, seed pod, branches plant, and 1000-seed weight are moderately correlated with seed yield, while pod plant and seed plant are strongly associated with seed yield. On the other hand, the pod length, branches plant, and gum content showed a positive but not significant relationship.
干旱是一种能够降低作物产量的非生物胁迫因素。它对作物减产有重大影响。对于处于胁迫下的作物，生物炭等有机调节剂可能会很有用。瓜尔豆（Cyamopsis tetragonoloba L.）是豆科的一年生豆科植物，对干旱和半干旱地区具有很强的适应性，在许多行业都有应用。田间试验采用裂区设计，三次重复，分为三个区组，分别为灌溉水平（Ir1=10，Ir2=14 和 Ir3=17 天灌溉周期）和生物炭（B1=0，B2=5 和 B3=10 吨/公顷）处理。目的是评估灌溉水平（Ir1=10，Ir2=14 和 Ir3=17 天灌溉周期）和生物炭（B1=0，B2=5 和 B3=10 吨/公顷）对生理特性[（叶绿素 a 和 b、叶绿素指数（SPAD）、相对叶片水含量（RWC）、电解质渗漏（EL）、冠层温度、叶片面积、水分利用效率（WUE）]、形态参数（茎长和直径、荚长、根和植株鲜重、根长）、产量构成（种子产量、分枝植物数、簇植物数、荚植物数、种子荚数、种子植物数、千粒重和胶含量）和叶片养分吸收（Ca、Mg、P、Na 和 K）的影响。观察到，在水分胁迫下，Ir3 灌溉处理的种子产量最高（1921.8 公斤/公顷）。然而，RGC-936 的荚植物（75.5）、种子植物（454.2）、种子产量（1871.1 公斤/公顷）、叶片面积（861.8 毫米）、SPAD（92.2）、Mg（49.8mg/g）、Na（43.3mg/g）和 P（0.49mg/g）最高。结果还表明，生物炭在形态特征方面比品种更有效。虽然品种对产量和产量构成有影响，但不同水平的灌溉对功能特性、生理和形态也有显著影响。生物炭的添加似乎对缓解水分胁迫和瓜尔生长以及叶片养分吸收有积极影响。根据皮尔逊相关分析，植物重量和长度、根重量和长度、茎直径、种子荚、分枝植物和千粒重与种子产量呈中度相关，而荚植物和种子植物与种子产量呈强相关。另一方面，荚长、分枝植物和胶含量呈正相关，但不显著。
