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[Objectives] The paper aims to clarify the dry matter accumulation and translocation of nutrient of rice plant under different soil tillage systems in a Chinese milk vetch(Astragalus sinicus L.) and double-cropping rice system. [Methods] The effects of different soil tillage systems on the dry matter accumulation and translocation of nitrogen(N), phosphorous(P) and potassium(K) of early and late rice plants by small area plot experimental method in double-cropping rice paddy field were analyzed in the present paper. The experiments were including four different soil tillage treatments:conventional tillage with residue incorporation(CT), rotary tillage with residue incorporation(RT), no tillage with residue retention(NT), rotary tillage with residue removed as a control(RTO). [Results] The results showed that the total dry matter accumulation of aboveground in different parts of rice plant and the amount of translocation of stem and leaves with RT and CT treatments were higher than those of the other treatments at mature stage of early rice and late rice. And the material translocation rate and material contribution rate of stem and leaves with CT, RT and NT treatments were higher than those of the RTO treatment at mature stage of early rice and late rice. Meanwhile, the contribution rate of material assimilation after heading stage with NT treatment was higher than that of the other treatments of early rice and late rice. The N accumulation amount in stem of rice plant with RT treatment was higher than those of the CT, NT and RTO treatments, and the N accumulation amount in panicle and aboveground of rice plant with CT, RT and NT treatments was higher than those of the RTO treatment at mature stage of early rice and late rice, respectively. And the P accumulation amount in stem and leaves of rice plant with CT and RT treatments was higher than those of the NT and RTO treatments, and the P accumulation amount in panicle and aboveground of rice plant with CT, RT and NT treatments was higher than those of the RTO treatment at mature stage of early rice and late rice, respectively. Meanwhile, the K accumulation amount in stem and aboveground of rice plant with CT and RT treatments was higher than that of the RTO treatment, and the K accumulation amount in leaves and panicle of rice plant with CT treatments was higher than that of the RTO treatment, respectively. [Conclusions] As a result, the total dry matter accumulation of aboveground in different parts of rice plant and the amount of translocation of stem and leaves were higher under application of residue incorporation, it is benefitial to the nutrients accumulation and translocation of rice plants by combined application of crop residues with soil conventional tillage, rotary tillage practices under double-cropping rice system in Southern China paddy field. [ABSTRACT FROM AUTHOR]

Rice is the most important food crop in China. Rice seed vigor is a complex quantitative trait controlled by multiple genes and it is of great significance to improve rice seed vigor for high yield, quality and efficiency of production under direct seedling rice. This paper reviewed the main research advances including evaluation index, gene identification and cloning, molecular regulation mechanism relate to rice seed vigor in recent years. Based on the molecular markers and map-based cloning, genome-wide association study(GWAS), high throughput sequencing, and omics techonology, more than twenty-three key genes related to seed vigor have been cloned, including transcription factor genes, metabolism-related genes of plant hormone ABA and GA. Through the balance of ABA and GA metabolism, it regulates maturing of embryos, seed dormancy and germination, seedling growth. It will be very helpful to improve genetics of rice seed vigor by molecular design breeding technology in the future. [ABSTRACT FROM AUTHOR]