Journal of Sichuan Agricultural University 

About: Journal of Sichuan Agricultural University is an academic journal. The journal publishes majorly in the area(s): Population & Gene. It has an ISSN identifier of 1000-2650. Over the lifetime, 344 publications have been published receiving 668 citations.

Effects of Different-growing-stage Shading on Rice Grain-filling and Yield

Abstract: A split-plot design was used as the main plot treatment to study the effects of different-growing-stage shading(tillering stage,elongating-heading stage and filling stage) on rice grain-filling and yield,with 16 hybrid rice combinations as the subplot treatments.The results showed that the grain filling and yield were obviously affected by shading.During tillering stage,shading made the effective panicles reduce significantly,the filled grain degree and filled grain percentage decline by 3.00%,4.03% respectively,and the yield by 17.34%.During elongating stage,shading made the filled grain degree and filled grain percentage higher than those of the control by 3.84% and 9.94%,but the yield declined by 41.35%.During filling stage,shading affected pollination and grain growth seriously,and made filled grain degree and filled grain percentage decline by 7.41% and 16.64% respectively,while the yield declined by 53.93%.At last,the cluster analysis showed that hybrid rice combinations Yifeng-8 and Gangyou 906 had better tolerance of shading.

Genetic analysis and mapping the flag leaf roll in rice (Oryza sativaL.)

Abstract: In this study, Genetic analysis for the flag leaf roll was carried out in F1 plants and a doubled haploid (DH) population derived from the inter-subspencific cross between ZYQ8 and JX17. The results show that flag leaf roll trait is controlled by two recessive genes. Based on a molecular linkage map of the DH population, the two genes were mapped on chromosomes 1 and 5. The gene on chromosome 1 might be the same as rl-1 of classical genetic linkage map; the one on chromosome 5 might represent new loci and new designation is suggested rl-7.

Impact of Low-light Stress on Leaves Characteristics of Rice after Heading

Abstract: A three replicate, split plot design was used with species as main plot treatments and shading as subplot treatments. Species treatments included Indica hybrid Ⅱ you 162, Dyou 68 and Gangyou 22. Shading treatments began after 10% panicles heading, and subplot treatments were wrapped with one or two layers of 49% shade or 69% shade. The leaves characteristics were measured. The leaves characteristics were obviously affected by the low light stress. The length and the width of leaves under low light stress were greater than those of the control. The average LAI of each species in 49% shade was higher than that of the control, and the LAI of each species in 69% shade was lower than that in 49% shade. The SLA of Dyou 68 and Gangyou 22 increased while the light density decreased. The chla, chlb, chl (a+b) increased, and chl a/b decreased while light density decreased. The relative dry matter weight of leaves in 49% shade or 69% shade was higher than that of the control.

Study on the change of organic acid synthetase activity during fruit development of navel orange ( Citrus sinensis Osbeck)

Abstract: The activity variance of enzymes related to organic acid metabolism and the relationship between enzymes and organic acid accumulation in pulp during development of Robertson Navle orange fruit were studied. The results showed: ①From June to August, the activity of citrate synthetase (CS) increased rapidly and reached the maximum in middle of August, then decreased rapidly. In middle of October, CS activity returned to rise and decreased again. ②From June to August, the activity of phosphoenolpyuvate carboxylase (PEPC) increased rapidly, in middle of August reached the maximum. After the fruit inflation stage, PEPC activity decreased rapidly and it didn't change on the whole in telophase and the mature stage. ③The variance tendency of activities of CS and PEPC were consistent with that of organic acid content. There was a significant positive correlation between the activity of CS or PEPC and organic acid, their correlation coefficients (r) were 0 9160 and 0 8779 respectively. These results proved that CO 2 fixation was a main pathway of organic acid synthesis in Navel orange fruit. They proved also that CS and PEPC were the key enzymes of organic acid synthesis. Efficiently inhibition of CS and PEPC activity could reduce the organic acid content of orange fruit.

Effect of Low light on Dry Matter Accumulation and Yield of Rice

Abstract: The effect of low-light stress after 10% panicles heading on accumulation, distribution and transformation of plant dry matters and panicle characteristics and Yield of three varieties of hybrid rice are studied. The results show that the production, distribution and transformation of plant dry matters are obviously affected by shading. The average net assimilation rate (NAR) and dry matters production per day in low light treatments are less than the control. On the contrary, the export and transformation percentage of the dry matters in stems and sheaths (EPMSS and TPMSS) increase under low-light stress. Under low-light stress, the distribution percentage of dry matter to leaves, stems and sheaths increase, and panicles decreased in relation to the control. Grains yield of rice is significantly affected by shading. The 49% and 69% shaded treatments produce a mean yield depression of 40.1% and 62.1%. The seed-setting rate is reduced 27.8% by 49%-shade and 44.2% by 69%-shade. The grains weight of low light treatments is significantly lower than the control.