Harran University, Faculty of Agriculture, Department of Soil Science & Plant Nutrition, Şanlıurfa, Turkey.
Department of Botany, GC University Faisalabad, Faisalabad, Pakistan.
Sci Rep. 2020 Apr 14;10(1):6432. doi: 10.1038/s41598-020-62669-6.
Soil amendments are known to promote several plant growth parameters. In many agro-ecosystems, water scarcity and drought induced phosphorus deficiency limits crop yield significantly. Considering the climate change scenario, drought and related stress factors will be even more severe endangering the global food security. Therefore, two parallel field trials were conducted to examine at what extent soil amendment of leonardite and humic acid would affect drought and phosphorus tolerance of maize. The treatments were: control (C: 100% A pan and 125 kg P ha), P deficiency (phosphorus stress (PS): 62.5 kg P ha), water deficit stress (water stress (WS): 67% A pan), and PS + WS (67% A pan and 62.5 kg P ha). Three organic amendments were (i) no amendment, (ii) 625 kg S + 750 kg leonardite ha and (iii) 1250 kg S + 37.5 kg humic acid ha) tested on stress treatments. Drought and P deficiency reduced plant biomass, grain yield, chlorophyll content, F/F, RWC and antioxidant activity (superoxide dismutase, peroxidase, and catalase), but increased electrolyte leakage and leaf HO in maize plants. The combined stress of drought and P deficiency decreased further related plant traits. Humic acid and leonardite enhanced leaf P and yield in maize plants under PS. A significant increase in related parameters was observed with humic acid and leonardite under WS. The largest increase in yield and plant traits in relation to humic acid and leonardite application was observed under combined stress situation. The use of sulfur-enriched amendments can be used effectively to maintain yield of maize crop in water limited calcareous soils.
土壤改良剂被认为可以促进几种植物生长参数。在许多农业生态系统中，水资源短缺和干旱引起的磷缺乏严重限制了作物产量。考虑到气候变化情景，干旱和相关压力因素将更加严重，危及全球粮食安全。因此，进行了两项平行田间试验，以研究程度土壤改良剂腐植酸和腐植酸会如何影响玉米的干旱和磷耐性。处理方法如下：对照（C：100% A pan 和 125kg P ha）、磷缺乏（磷胁迫（PS）：62.5kg P ha）、水分亏缺胁迫（水分胁迫（WS）：67% A pan）和 PS+WS（67% A pan 和 62.5kg P ha）。三种有机改良剂分别为：（i）无改良剂；（ii）625kg S+750kg 风化煤 ha；（iii）1250kg S+37.5kg 腐植酸 ha，对胁迫处理进行了测试。干旱和磷缺乏降低了植物生物量、籽粒产量、叶绿素含量、F/F、RWC 和抗氧化活性（超氧化物歧化酶、过氧化物酶和过氧化氢酶），但增加了电解质泄漏和叶片 HO 在玉米植株中。干旱和磷缺乏的联合胁迫进一步降低了相关植物性状。腐植酸和风化煤在 PS 下提高了玉米叶片的 P 和产量。在 WS 下，观察到腐植酸和风化煤对相关参数有显著增加。腐植酸和风化煤联合应用对产量和植物性状的增加最大。在有限的石灰性土壤中，使用富含硫的改良剂可以有效地维持玉米作物的产量。
