Pre-sowing Seed Treatments in Direct-seeded Early Rice: Consequences for Emergence, Seedling Growth and Associated Metabolic Events under Chilling Stress

Abstract

Double direct-seeding for double rice cropping is a simplified, labor saving, and efficient cropping system to improve multiple-crop index and total rice production in central China. However, poor crop establishment of direct-seeded early rice due to chilling stress is the main obstacle to wide spread of this system. A series of experiments were conducted to unravel the effects of pre-sowing seed treatments on emergence, seedling growth and associated metabolic events of direct-seeded early rice under chilling stress. Two seed priming treatments and two seed coating treatments were used in all the experiments. A non-treated control treatment was also maintained for comparison. In both the field and growth chamber studies, seed priming with selenium or salicylic acid significantly enhanced the emergence and seedling growth of rice compared with non-treated control. Nevertheless, such positive effects were not apparent for seed coating treatments. Better emergence and vigorous seedling growth of rice after seed priming was associated with enhanced α-amylase activity, higher soluble sugars contents, and greater respiration rate in primed rice seedlings under chilling stress. Taking together, these findings may provide new avenues for understanding and advancing priming-induced chilling tolerance in direct-seeded early rice in double rice cropping system.

High‐density planting with lower nitrogen application increased early rice production in a double‐season rice system

“…Double rice ( Orvza sativa L.) cropping is a typical rice production system in China, and is considered an efficient method for increasing both the multiple‐crop index and total rice production (Wang et al., ). Planting density and nitrogen (N) fertilization are two critical factors varied among rice cropping systems to improve yield (Dobermann et al., ; Fagade & De Datta, ).…”

“…Double rice (Orvza sativa L.) cropping is a typical rice production system in China, and is considered an efficient method for increasing both the multiple-crop index and total rice production (Wang et al, 2016). Planting density and nitrogen (N) fertilization are two critical factors varied among Abbreviations: AE, agronomic efficiency; CGR, crop growth rate; CK, control; FH-MA, full-heading stage to maturity; HI, harvest index; LA, leaf area; PEP, partial factor productivity of applied nitrogen; PL-FH, panicle initiation to full-heading stage; T1, high basic seedling with low N input; T2, higher basic seedling with low N input; TR-PI, transplanting to panicle initiation stage.…”

Effects of extracts of Oxalis barrelieri L. and Cymbopogon citratus stapf, coupled with NaCl sorting on; seed health, germination and seedlings vigor of rice (Oryzae sativa L).

“…The plant extracts used in this research could therefore be little more involved in the stimulation of germination than increase in vigor; this being realized through the stimulation of α-amylase activity, the liberation of free soluble sugars and increase in the seeds respiration frequency (Wang et al, 2016) as a result of, the action of their secondary metabolites.…”

Direct Seed Planting System and Giving Liquid Organic Fertilizer as A New Method to Increase Rice Yield and Growth (Oryza sativa L.)

“…To obtain optimal results, perfect tillage is needed to facilitate the growth of rice plants in the generative growth phase. Water management through drainage is carried out to prevent the seeds from being washed away during the plant growth process (Wang et al, 2016).…”