随着全球气候变化,生育期光照不足已成为制约玉米产量的主要因素之一。外源激素的施用是缓解非生物胁迫对作物生产力的可行措施。在这项研究中,进行了田间试验,以研究喷施外源激素对产量的影响,干物质(DM)和氮(N)积累,2021年和2022年弱光胁迫下鲜食糯玉米叶片碳和氮代谢。包括自然光(CK)在内的五种治疗方法,授粉后弱光(Z),喷水(ZP1),使用两个杂种suyunuo5(SYN5)和jingkenuoo2000(JKN2000)在授粉后的弱光下建立了外源植酸酶Q9(ZP2)和6-苄基腺嘌呤(ZP3)。结果表明,弱光胁迫显著降低了平均鲜穗产量(49.8%),鲜粮产量(47.9%),DM(53.3%)和氮积累(59.9%),增加了谷物的水分含量。净光合速率(Pn),授粉后穗叶的蒸腾速率(Tr)在Z下降低。弱光降低了RuBPCase和PEPCase的活性,硝酸还原酶(NR),谷氨酰胺合成酶(GS),谷氨酸合酶(GOGAT),超氧化物歧化酶(SOD),耳朵叶片中的过氧化氢酶(CAT)和过氧化物酶(POD),并增加丙二醛(MDA)的积累。JKN2000的降幅更大。而ZP2和ZP3处理提高了鲜穗产量(17.8%,25.3%),鲜粮产量(17.2%,29.5%),DM(35.8%,44.6%)和N(42.5%,52.4%)积累,与Z相比,降低了谷物水分含量。Pn,Tr在ZP2和ZP3下增加。此外,ZP2和ZP3处理提高了RuBPCase的活性,PEPCase;NR,GS,GOGAT;SOD,CAT,POD在耳叶,灌浆期MDA含量降低。结果还显示ZP3的缓解作用大于ZP2,且对JKN2000的改善作用更为显著。
Insufficient light during the growth periods has become one of the main factors restricting maize yield with global climate change. Exogenous hormones application is a feasible measure to alleviate abiotic stresses on crop productivity. In this study, a field trial was conducted to investigate the effects of spraying exogenous hormones on yield, dry matter (DM) and nitrogen (N) accumulation, leaf carbon and N metabolism of fresh waxy maize under weak-light stress in 2021 and 2022. Five treatments including natural light (CK), weak-light after pollination (Z), spraying water (ZP1), exogenous Phytase Q9 (ZP2) and 6-benzyladenine (ZP3) under weak-light after pollination were set up using two hybrids suyunuo5 (SYN5) and jingkenuo2000 (JKN2000). Results showed that weak-light stress significantly reduced the average fresh ear yield (49.8%), fresh grain yield (47.9%), DM (53.3%) and N accumulation (59.9%), and increased grain moisture content. The net photosynthetic rate (Pn), transpiration rate (Tr) of ear leaf after pollination decreased under Z. Furthermore, weak-light decreased the activities of RuBPCase and PEPCase, nitrate reductase (NR), glutamine synthetase (GS), glutamate synthase (GOGAT), superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) in ear leaves, and increased malondialdehyde (MDA) accumulation. And the decrease was greater on JKN2000. While ZP2 and ZP3 treatments increased the fresh ear yield (17.8%, 25.3%), fresh grain yield (17.2%, 29.5%), DM (35.8%, 44.6%) and N (42.5%, 52.4%) accumulation, and decreased grain moisture content compared with Z. The Pn, Tr increased under ZP2 and ZP3. Moreover, the ZP2 and ZP3 treatments improved the activities of RuBPCase, PEPCase; NR, GS, GOGAT; SOD, CAT, POD in ear leaves, and decreased MDA content during grain filling stage. The results also showed the mitigative effect of ZP3 was greater than ZP2, and the improvement effect was more significant on JKN2000.