In order to improve crop productivity, farmers should have strategies for higher quantity and quality of forage without excessive inputs, like irrigation water. In order to assess forage quality of Amaranthus caudatus in response to irrigation levels (irrigation after 70, 140 and 210 mm of evaporation from class A pan) as main plots and foliar sprays of abscisic acid (ABA; 50 μM), salicylic acid (SA; 3 g l–1) and potassium sulfate (PS; 3 g l–1) as subplots. A water shortage from 70 to 210 mm of evaporation decreased the stomata conductance and leaf-area index, but the crude protein concentration, dry matter digestibility, leaf/stem ratio, forage yield and total nitrogen were increased from 70 to 140 and then decreased. Using deficit irrigation for amaranth can reduce water usage without significant yield loss, so that water use efficiency remains at the relatively high levels. Leaf water potential, relative water content, leaf-area index, total chlorophyll, carotenoid, crude protein, dry matter digestibility, leaf/stem ratio and forage yield were increased by foliar sprays. Significant reduction in forage quality occurred at delayed harvest. Forage yield of potassium sulfate treated under severe stress was increased by 29% and 56% at flowering and seed set stages, respectively.

中文翻译：

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不同水分胁迫条件下生长调节剂对马尾苋牧草产量和品质的有益影响

为了提高作物生产力，农民应该制定战略，在不过度投入的情况下提高草料的数量和质量，如灌溉水。为了评估 Amaranthus caudatus 的牧草质量响应灌溉水平（从 A 级锅蒸发 70、140 和 210 毫米后灌溉）作为主要地块和叶面喷洒脱落酸（ABA；50 μM）、水杨酸（SA ; 3 gl-1) 和硫酸钾 (PS; 3 gl-1) 作为子图。蒸发量从 70 毫米到 210 毫米的缺水会降低气孔导度和叶面积指数，但粗蛋白浓度、干物质消化率、叶茎比、牧草产量和总氮从 70 增加到 140，然后下降。对苋菜使用亏缺灌溉可以减少用水量而不会造成显着的产量损失，使水资源利用效率保持在较高水平。叶面喷洒提高了叶水势、相对含水量、叶面积指数、总叶绿素、类胡萝卜素、粗蛋白、干物质消化率、叶茎比和牧草产量。延迟收获时，牧草质量显着下降。在严重胁迫下，硫酸钾在开花期和结实期的牧草产量分别增加了 29% 和 56%。