[ Objective ] The paper was to study the density restriction effects of reproductive rate of rice brown planthopper (BPH) population in super indiea and japonica hybrid rice Yongyou 6. [Method] Different amounts of ...[ Objective ] The paper was to study the density restriction effects of reproductive rate of rice brown planthopper (BPH) population in super indiea and japonica hybrid rice Yongyou 6. [Method] Different amounts of rice brown planthoppor were released to super indiea and japonica hybrid flee Yongyou 6 during fillering, booting and gain filling stage, respectively. The reproductive rate and variation dynamics of rice brown planthoppor in super rice was also investigated and analyzed. [Result] Tillering stage: the population quantity of rice brown planthoppor during booting and gain filling stage gradually increased with the increasing basal amount of its population during tillering stage; when the population density of rice brown planthopper during grain filling stage reached a certain limit ( 〉 250 head/cluster), the population density during milking stage showed decrease trend with the increasing of such density; the development of rice brown planthoppor population in super rice Yongyou 6 showed the characteristics of fast in middle and slow in two ends. Booting stage: the development of rice brown planthopper pop- ulation from booting to gain filling stage increased with the increasing basal amount of density, and their correlation during milking stage was not significant; flee brown planthopper population still had high reproduction capacity in the middle and late stage of super rice, which had latent risk on rice yield. Gain filling stage : when population density of rice brown planthopper 〈 70 head/cluster, the development of it population increased with the increase of basal amount of density, which had great threat to yield. [ Conclusion] The result provided theoretical basis for establishment and improvement of monitoring early warning system, cost-ef- fective control of occurrence and damage of rice brown planthopper, and improvement of the sustained control ability against rice brown planthopper.展开更多
糙米经不同剂量的60Co-γ辐照后,恒温(15±0.5)℃储藏1年,每3个月进行1次品质测定,并分析辐照剂量对储藏糙米各指标的影响。结果表明,储藏1年后,糙米表面颜色b值升高,储藏期间b值有波动,1.0 k Gy和2.0 k Gy的辐照后,糙米表面颜色b...糙米经不同剂量的60Co-γ辐照后,恒温(15±0.5)℃储藏1年,每3个月进行1次品质测定,并分析辐照剂量对储藏糙米各指标的影响。结果表明,储藏1年后,糙米表面颜色b值升高,储藏期间b值有波动,1.0 k Gy和2.0 k Gy的辐照后,糙米表面颜色b值显著增加(P<0.05),大米呈现发黄趋势;L值随着辐照剂量的增加而降低(储藏时间对L值没有显著影响);经1.0 k Gy和2.0 k Gy辐照的糙米感官评定颜色项得分显著低于对照组(P<0.05);脂肪酸值随着储藏时间延长持续上升,辐照剂量与脂肪酸值无明显相关性(P>0.05);溶解度和膨胀力都随着储藏时间延长而升高,第9个月达到峰值,随辐照剂量的增大,溶解度和膨胀力增大,米饭质构软化,米饭软硬度得分升高;糙米菌落总数含量随着储藏时间延长逐渐上升,但辐照剂量与菌落总数极显著负相关(P<0.01)。低剂量(0.2~0.5 k Gy)水平的辐照可显著优化储藏糙米理化指标,提高感官品质。展开更多
文摘[ Objective ] The paper was to study the density restriction effects of reproductive rate of rice brown planthopper (BPH) population in super indiea and japonica hybrid rice Yongyou 6. [Method] Different amounts of rice brown planthoppor were released to super indiea and japonica hybrid flee Yongyou 6 during fillering, booting and gain filling stage, respectively. The reproductive rate and variation dynamics of rice brown planthoppor in super rice was also investigated and analyzed. [Result] Tillering stage: the population quantity of rice brown planthoppor during booting and gain filling stage gradually increased with the increasing basal amount of its population during tillering stage; when the population density of rice brown planthopper during grain filling stage reached a certain limit ( 〉 250 head/cluster), the population density during milking stage showed decrease trend with the increasing of such density; the development of rice brown planthoppor population in super rice Yongyou 6 showed the characteristics of fast in middle and slow in two ends. Booting stage: the development of rice brown planthopper pop- ulation from booting to gain filling stage increased with the increasing basal amount of density, and their correlation during milking stage was not significant; flee brown planthopper population still had high reproduction capacity in the middle and late stage of super rice, which had latent risk on rice yield. Gain filling stage : when population density of rice brown planthopper 〈 70 head/cluster, the development of it population increased with the increase of basal amount of density, which had great threat to yield. [ Conclusion] The result provided theoretical basis for establishment and improvement of monitoring early warning system, cost-ef- fective control of occurrence and damage of rice brown planthopper, and improvement of the sustained control ability against rice brown planthopper.
文摘糙米经不同剂量的60Co-γ辐照后,恒温(15±0.5)℃储藏1年,每3个月进行1次品质测定,并分析辐照剂量对储藏糙米各指标的影响。结果表明,储藏1年后,糙米表面颜色b值升高,储藏期间b值有波动,1.0 k Gy和2.0 k Gy的辐照后,糙米表面颜色b值显著增加(P<0.05),大米呈现发黄趋势;L值随着辐照剂量的增加而降低(储藏时间对L值没有显著影响);经1.0 k Gy和2.0 k Gy辐照的糙米感官评定颜色项得分显著低于对照组(P<0.05);脂肪酸值随着储藏时间延长持续上升,辐照剂量与脂肪酸值无明显相关性(P>0.05);溶解度和膨胀力都随着储藏时间延长而升高,第9个月达到峰值,随辐照剂量的增大,溶解度和膨胀力增大,米饭质构软化,米饭软硬度得分升高;糙米菌落总数含量随着储藏时间延长逐渐上升,但辐照剂量与菌落总数极显著负相关(P<0.01)。低剂量(0.2~0.5 k Gy)水平的辐照可显著优化储藏糙米理化指标,提高感官品质。