Bell pepper cultivation under different irrigation strategies in soil with and without mulching

ABSTRACT This study aimed to evaluate productive, physiological and phytotechnical characteristics of bell pepper under different irrigation strategies, in soil with mulch (polyethylene film, black on bottom, white on top) and without mulching. The experimental design was of randomized blocks with four replicates, arranged in split plot scheme; plots consisted of treatments with and without mulching, and in the subplots ten irrigation strategies = 1) 125% of crop evapotranspiration (ETc); 2) 100% of ETc; 3) 75% of ETc; 4) 50% of ETc, both in vegetative phase (FI) and production phase (FII); 5) regulated deficit irrigation (RDI); with 50% of ETc in FI and 100% of ETc in FII; 6) RDI with 100% of ETc in FI and 50% of ETc in FII; 7) RDI with 75% of ETc in FI and 100% of ETc in FII; 8) RDI with 100% of ETc in FI and 75% of ETc in FII; 9) RDI with 125% of ETc in FI and 75% of ETc in FII; 10) RDI with 75% of ETc in FI and 125% of ETc in FII. Two phytotechnical and one physiological evaluations were done during the phases of development and production. Moreover, we determined productivity and water-use efficiency 90 days after seedling transplanting. Plants maintained quantum efficiency and chlorophyll a content close to the ideal. Mulching provided higher number of fruits in comparison to plants grown in bare soil. Diameter, mass and length of the fruits as well as peel thickness were higher at the first two harvests. Irrigation at 50% of ETc in mulched soil provided higher productivity using less water, increasing water-use efficiency.

摘要 本研究旨在评估底黑面白聚乙烯地膜覆盖栽培与裸地栽培条件下，不同灌溉策略对甜椒产量、生理及农艺性状的影响。试验采用裂区设计的随机区组方案，设置4次重复；主区设置覆盖栽培与裸地两个处理，副区则包含10种灌溉策略：1）全生育期灌水量为作物蒸散量（crop evapotranspiration，简称ETc）的125%；2）全生育期灌水量为ETc的100%；3）全生育期灌水量为ETc的75%；4）全生育期灌水量为ETc的50%（上述处理在营养生长期（vegetative phase，简称FI）与结果期（production phase，简称FII）采用统一灌水量）；5）调亏灌溉（regulated deficit irrigation，简称RDI）：营养生长期灌50% ETc、结果期灌100% ETc；6）调亏灌溉：营养生长期灌100% ETc、结果期灌50% ETc；7）调亏灌溉：营养生长期灌75% ETc、结果期灌100% ETc；8）调亏灌溉：营养生长期灌100% ETc、结果期灌75% ETc；9）调亏灌溉：营养生长期灌125% ETc、结果期灌75% ETc；10）调亏灌溉：营养生长期灌75% ETc、结果期灌125% ETc。在作物生育期与结果期分别开展2项农艺性状与1项生理指标测定。此外，于幼苗定植90天后测定作物产量与水分利用效率。试验结果表明，供试植株的量子效率与叶绿素a含量维持在接近理想水平；地膜覆盖处理的单株结果数显著高于裸地栽培植株；前两次采收的果实直径、单果质量、果长及果皮厚度均更高。在地膜覆盖条件下，灌水量为50% ETc的灌溉策略可在减少灌水量的同时获得更高产量，提升水分利用效率。