壮秆剂及用量对水稻产量和抗倒伏能力的影响

以籼粳杂交稻品种甬优2640、超级稻南粳9108为供试材料,设置壮秆剂A(壮秧剂∶速效硅∶生物炭=1.0∶0.5∶1.0)5个处理(A-1:18.75 kg hm~(–2)、A-2:37.5 kg hm~(–2)、A-3:56.25 kg hm~(–2)、A-4:75 kg hm~(–2)、A-5:93.75 kg hm~(–2)),壮秆剂B("杰伟"牌水稻生长调节剂)5个处理(B-1:7.5 kg hm~(–2)、B-2:15 kg hm~(–2)、B-3:22.5 kg hm~(–2)、B-4:30 kg hm~(–2)、B-5:37.5 kg hm~(–2))。在齐穗后30 d观测水稻基部第1节间(N1)、第2节间(N2)、第3节间(N3)、第4节间(N4)抗倒伏能力和主要物理性状,比较研究壮秆剂不同用量对水稻产量及抗倒伏能力的影响。两年试验结果表明,壮秆剂A对水稻产量及抗倒伏能力的影响要优于壮秆剂B,随着壮秆剂用量的增加水稻产量呈先增后减的趋势,其中A-3处理产量最高,其原因在于每穗粒数、结实率、千粒重均有所增加,壮秆剂B中B-3产量最高,壮秆剂A增产效果优于B的原因在于千粒重的增加。随着壮秆剂用量的增加,各节间倒伏指数呈现先减后增趋势,其中A-3、A-4处理的N_2、N_3倒伏指数显著小于对照。进一步分析壮秆剂A与B抗倒伏能力增强的原因在于抗折力的增加,壮秆剂A主要是通过增加N_1、N_2、N_3节间茎秆粗度、茎壁厚度和节间充实度增强了抗倒伏能力,壮秆剂B主要是增加N_1、N_2、N_3节间茎壁厚度来增强抗倒伏能力,两者比较壮秆剂A效果更明显。

Effect of Variety and Application Amount of Stalk Strengthening Agent on Yield and Lodging Resistance in Rice

A field experiment was conducted using indica-japonica hybrid rice Yongyou 2640 and super rice cultivar Nanjing 9108, with five treatments (A-1: 18.75 kg ha^–1, A-2: 37.5 kg ha^–1, A-3: 56.25 kg ha^–1, A-4: 75.00 kg ha^–1, A-5: 93.75 kg ha^–1) of stalk strengthening agent A (seedling strengthening agent : quick acting silicon : biochar = 1.0 : 0.5 : 1.0), and five treatments (B-1: 7.5 kg ha^–1, B-2: 15 kg ha^–1, B-3: 22.5 kg ha^–1, B-4: 30 kg ha^–1, B-5: 37.5 kg ha^–1) of stalk strengthening agent B (Jiewei growth regulators of rice). In the thirtieth days after full heading, the lodging resistance of the first basal internode (N₁), the second basal internode (N₂), the third basal internode (N₃), the fourth basal internode (N₄), and main physical characteristics were studied. The effect of stalk strengthening agent A on yield and lodging resistance was better than that of stalk strengthening agent B. With the increase of application amount of stalk strengthening agent, the yield increased firstly and decreased then, with the highest yield in A-3, resulting from the increase of spikelets per panicle, seed-setting rate and 1000-grain weight, and in B-3 resulting from the increase of 1000-grain weight. In contrary, lodging index decreased firstly and increased then, with the significant decrease of the second basal internode and the third basal internode of A-3 and A-4. The reason lodging resistance increased was the increase of breaking resistance, through the increase of culm diameter, culm wall thickness and plumpness in N₁, N₂, and N₃ by stalk strengthening agent A, and of culm wall thickness in N₁, N₂, and N₃ by stalk strengthening agent B, showing advantage effect of agent A than agent B.