缓/控释肥对杂交水稻根系形态、生理特性和产量的影响

以杂交中稻F优498为试验材料，采用两因素裂区试验研究4 种氮肥种类（尿素一道清、尿素常规运筹、硫包膜缓释肥、树脂包膜控释肥）在不同移栽秧龄施肥对水稻不同生育期根系形态及籽粒产量的影响。结果表明，在秧苗3叶1心、 5叶1心移栽时水稻在结实期的总根长、根系体积和根系伤流强度比7 叶1 心移栽时高。与施用尿素相比，施用缓/ 控释肥显著增加了根干重、总根长、根系体积和根系伤流强度。在不同移栽秧龄下，施用缓/控释肥均能促进水稻根系生长并向土壤深层分布，保持根系活力。相关分析表明， 水稻籽粒产量与抽穗后的根干重、总根长、根系表面积、伤流强度和10 cm以下的根系分布比例呈显著或极显著正相关。综合根系形态生理与产量表现，5 叶1心移栽、施用树脂包膜控释肥，为本试验的最佳处理。

Effects of slow/controlled release fertilizers on root morphological and physiological characteristics of rice

Effects of different types of nitrogen fertilizer, including conventional urea applied as single basal application (F1), normal urea management (F2), sulfur coated slow release fertilizer (F3) and resin coated controlled release fertilizer (F4), and different transplanting seedling ages, including 3-leaf (T1), 5-leaf (T2) and 7-leaf (T3), on root morphological and physiological characteristics of rice (cultivar of F you 498) were studied using the split block experiment design. The slow/controlled release fertilizer whose nutrient release rate is basically consistent with fertilizer requirement of crop is used as a new type fertilizer with long time affections. In some crops, it realizes one time basal fertilizer application and thus simplifies fertilizer application technology thoroughly. The results show that nitrogen fertilizer can alleviate adverse impact of later transplanting on the growth of roots. The total root lengths, root volumes and root bleeding intensities of the 3-leaf and 5-leaf are higher than those of the 7-leaf at the bearing stage. Compared to conventional urea application, applying the slow controlled release fertilizer increases root dry weight, total root length, root volume and root bleeding intensity significantly in the late growing stages which are the critical period for rice growth. The root dry weight, total root length, total root surface area, root bleeding intensity and root weight distribution ratio below 10 cm soil layer have a significant relationship with the yield at the maturing stage. Different transplanting seedling ages and nitrogen types affect rice growth mainly through total root length, root volume and root bleeding intensity. At different transplanting seedling ages, application of slow controlled release fertilizer can increase the yield by promoting root growth and deep distribution, keeping high root activities. In combination with morphological and physiological characteristics and the yield, the 5-leaf transplanting seedling age and resin coated controlled release fertilizer can be the references for alleviating the contradiction of proceeding crops and nitrogen use methods in local region.