Effects of Nitrogen Application Amount during Various Periods on Yield of High Grade Hybrid Rapeseed

[Objective] The paper was to study the nitrogen application amount and nitrogen application model for high grade hybrid rapeseed （Brassica napus L.） to get high yield. [Method] With ＂Youyan 599＂ and ＂Sanbei 98＂ as materials, using quadratic regression orthogonal gyration combination design, the impact of nitrogen application amount during various periods on rapeseed yield was studied. [Result] The combinations of factors to obtain the highest yield index （2 898.211 kg / hm 2 ） of ＂Youyan 599＂ were as follows： living rape fertilizer 89.27 kg / hm 2 , opening fertilizer 120 kg / hm 2 , 12 th lunar month fertilizer 101.12 kg / hm 2 , total nitrogen application amount 310.39 kg / hm 2 . The proportions of living rape fertilizer, opening fertilizer and 12th lunar month fertilizer were 28.76%, 38.66% and 32.58%, respectively. The combinations of factors to obtain the highest yield index （2 870.14 kg/hm 2 ） of ＂Sanbei 98＂ were as follows： living rape fertilizer 120 kg / hm 2 , opening fertilizer 120 kg / hm 2 , 12 th lunar month fertilizer 37.55kg / hm 2 , total nitrogen application amount 277.55 kg / hm 2 . The proportions of living rape fertilizer, opening fertilizer and 12 th lunar month fertilizer were 43.24%, 43.24% and 13.53%, respectively. The combinations of factors to obtain the highest yield index of two combined varieties （2 813.82 kg/hm 2 ）were as follows： living rape fertilizer 120 kg/hm 2 , opening fertilizer 120 kg/hm 2 , 12 th lunar month fertilizer 76.23 kg/hm 2 , total nitrogen application amount 316.23 kg/hm 2 . The proportions of living rape fertilizer, opening fertilizer and 12 th lunar month fertilizer were 37.95% , 37.95% and 24.11% , respectively. [Conclusion] The paper provided theoretical basis for high yield cultivation of high grade hybridized rapeseed.

Ecological Adaptability of New Hybrid Rapeseed Varieties in Sichuan Hilly Areas

[Objective] The aim was to explore rapeseed varieties adapting to local conditions, with optimal yielding capacity and growth period. [Method] The research performed analysis on yield, yielding components, and interaction effects in different groups and test sites based on hybrid rapeseeds in Mianyang during 2012-2015.[Conclusion] Mianyou 33, Mianyou 88 and Mianyou 309 showed insignificant differences in yield. The analysis of variance suggested that yield of Mianyou 309 was the highest and the variety was suitable to be planted in high erucic acid rapeseed bases. Mianyou 88 and Mianyou 33 are double-low varieties, characterized by high and stable yielding. [Conclusion] The research provides references for rapeseed production in hilly areas in Sichuan Province.

Effect of Cultivation Conditionss on Quality Parameters of High Grade Hybrid Rape of Brassica napus L.

[Objective] This study aimed to investigate the combined effects of sowing date, plant density, nitrogenous fertilizer, phosphorus fertilizer and potassium fertilizer on quality parameters of high grade hybrid rapeseed. [Method] By using Youyan 599 and Sanbei 98 as experimental materials, quadratic orthogonal rotation combination with five factors was designed for this study. [Result] Erucic acid content was nega- tively correlated with sowing date and nitrogen fertilizer, positively correlated with plant density. Glucosinolate content was negatively correlated with sowing date, positively correlated with potash fertilizer amount. Oil content was negatively correlated with sowing date and nitrogen fertilizer amount, positively correlated with plant density and potash fertilizer amount. Protein content was positively correlated with sowing date and nitrogen fertilizer amount, negatively correlated with plant density and potash fer- tilizer amount. Oleic acid content was negatively correlated with phosphate fertilizer amount, positively correlated with nitrogen fertilizer amount. Palmitic acid was nega- tively correlated with potash fertilizer amount, positively correlated with sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount in Youyan 599, but negatively correlated with sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount in Sanbei 98. Stearic acid content was posi- tively correlated with sowing date, plant density, nitrogen fertilizer amount and phos- phate fertilizer amount. Linoleic acid was positively correlated with density and nitroge- nous fertilizer, but negatively correlated with potash fertilizer amount. Linolenic acid was positively correlated with nitrogen fertilizer amount and potash fertilizer amount. Eicosenoic acid was negatively correlated with sowing date. There were positive cor- relations and negative correlations among cultivation conditions and quality parame- ters, and the positive correlations and negative correlations could counteract each other. Expression of quality parameters for each treatment was the combined effect. Among the 50 pairs of simple correlations of five cultivation factors and ten quality parameters, 26 pairs were consistent between two varieties, 24 pairs of simple corre- lation were not. Sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount showed significant influence on erucic acid of two varieties, but small effect on palmitic acid. [Conclusion] The combined effect of the five cultivation factors could not fundamentally improve the quality traits of high grade hybrid rapeseed.