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Effects of photoperiod treatment for different fall-dormant alfalfa on abscisic acid (ABA) levels
2005
Wang Chengzhang,Han Jinfeng,Hu Xifeng
苜蓿(Medicago satire)秋眠性(fall dormancy)是苜蓿在秋季因日照长度变短和气温下降时的一种适应性生长特性,这种生长特性与苜蓿的抗寒性和生产性能相关。自20世纪20年代Oakley发现苜蓿秋眠性以来,国外许多学者相继对不同秋眠性苜蓿品种的生长习性、根系形态、生产能力、抗寒性等进行了大量研究。结果表明,秋眠性苜蓿秋季刈割后顶端生长长度很短,产量低,但越冬性增强,非秋眠型苜蓿则相反。
Показать больше [+] Меньше [-]Comprehensive evaluation of new varieties of insect-resistant hybrid cotton by grey association degree
2005
Bao Lisheng
通过筛选和搭配种植不同类型品种;应用水稻移栽前农田养草灭草,移栽后水层控草、辅以稻田养鸭,后期人工拔草补治等技术进行草害防治;与豆科作物轮作、种植根瘤菌接种的绿肥作物培肥土壤等综合技术提高有机稻米生产能力,在有机稻米生产中取得了显著成效。
Показать больше [+] Меньше [-]Effect of water stress on photosynthetic characteristics and yield character of two wheat cultivars with different drought-resistance
2005
Lu Lihua, Li Yanming, Hu Yukun
以河农859和豫麦49为材料,在不同水分处理下研究了2个品种功能叶的光合速率(Pn)、蒸腾速率(TR)和产量性状。结果表明,在拔节期、灌浆前期和生育后期,各处理0~20cm、20~40cm土层分别处于不同程度的水分胁迫条件下,叶片Pn和TR一般以河农859的较高,且其叶片Pn和TR下降百分率均小于豫麦49。2个品种叶片的Pn和TR均以春季浇2水(拔节水+灌浆水)的S3处理具有优势。从产量性状分析,河农859籽粒产量明显高于豫麦49,其浇2水的S3处理比浇1水(拔节水)的S2处理增产,但差异不显著;而豫麦49S3处理的产量显著高于S2处理和S1处理(冻水+拔节水)。表明河农859抗旱性较强,有限供应的水分就能使其获得较高的产量,而豫麦49只有在供水充足的条件下才能发挥其高产潜力。
Показать больше [+] Меньше [-]Effects of drought stress on induced protein in the different drought resistance alfalfa leaf
2005
Kang Junmei, Yang Qingchuan, Fan Fencheng
利用SDS-PAGE电泳分析法探讨干旱对供试苜蓿品种叶片可溶性蛋白的变化及其与干旱强度的关系。结果表明:可溶性蛋白的变化与干旱强度有直接关系,随着干旱胁迫强度的增加某些可溶性蛋白的变化表现为先增强后减弱;干旱胁迫诱导蛋白量的变化各异,抗旱性强的品种能诱导基因更强的表达以适应干旱胁迫,而抗旱性较弱的品种可能减弱或丧失其自我调节能力,产生的干旱诱导蛋白量比前者少;在干旱15 d时,抗旱性强的品种均被诱导产生新的蛋白带,只有两个抗旱性弱的品种出现该谱带;供试苜蓿品种的抗旱性存在明显的遗传多样性,其中抗旱性强的品种是苜蓿抗旱性选育的重要种质资源。
Показать больше [+] Меньше [-]Selection of a new variety of Adzuki bean (Vibnaangularis),Bao 9326-16
2005
Wang Shun, Li Caiju, Gao Yiping
保9326-16是保定市农业科学研究所育成的红小豆新品种。在育种方法上,根据遗传距离远的亲本杂交后代分离范围广、产生优系机率大的原理及遗传学性状互补原理,利用阶梯式杂交方法,成功地将多个亲本的优良性状综合于一体。后代材料的处理上,根据遗传性状之间遗传力不同的特点,早世代选择株型、株高、单株粒重、百粒重、生育期、抗逆性、粒型粒色,晚世代进行丰产性鉴定。依据育种目标,优中选优,1997年选出稳定品系保9326-16。该品系兼具冀红1号、冀红3号、台9红小豆、保8824-17红小豆的优良性状,与当前河北省区试对照种冀红4号相比,在高产、稳产、商品性状、抗旱、耐涝及适应性方面,都获得了较大的提高,适合中、高水肥地夏播,改变了高水肥地不能种植红小豆的历史。该品系2004年9月通过了河北省科技厅的成果鉴定。
Показать больше [+] Меньше [-]Parasitic fitness of Phytophthora infestans isolates from some potato areas of China
2005
Hou Shuying, Wei Changshuan, Xu Kuo
采用离体叶片接种法,用2个马铃薯品种:春薯4号(对马铃薯晚疫病菌表现高度抗病)和津引8号(对马铃薯晚疫病菌表现高度感病)对采自中国马铃薯主产区(河北、云南、四川、黑龙江)的60个马铃薯晚疫病菌菌株进行了致病性(侵染率、病斑面积、产孢能力)和寄生适合度的测定。结果表明:菌株的致病性、寄生适合度和其地域来源有一定的相关性,来源于河北的菌株致病性和寄生适合度最强,而来源于四川的菌株致病性和寄生适合度最弱。
Показать больше [+] Меньше [-]Effect of energy diet on the expression of PC and PEPCK mRNA in the liver of periparturient cows
2005
Li Hongmei,Li Yanfei,Xia Cheng
本研究目的在于观测干奶期不同能量摄入对围产期健康奶牛肝糖异生关键酶――丙酮酸羧化酶(PC)和磷酸烯醇式丙酮酸羧激酶(PEPCK)基因表达的影响。将健康围产期奶牛30头随机分为3组,于产前第28天分别饲喂奶牛标准日粮(能量摄入100%组)、标准日粮增加20%日粮(能量摄入120%组)和标准日粮减少20%日粮(能量摄入80%组),产后各组奶牛均饲喂标准的产奶日粮,至产后第56天结束。使用定量PCR方法检测分别于-28 d、-14 d、+1 d、+14 d、+28 d、+56 d采集的奶牛肝脏活体样品中PC和PEPCK mRNA表达水平。试验结果显示,PC mRNA丰度在产前28 d~产后56 d,低能组奶牛最高;PEPCK mRNA丰度在产后1 d~14 d低能组奶牛降低,产前28 d~14 d和产后28 d~56 d低能组奶牛最高。说明干奶期低能饲喂奶牛,可以增强围产期奶牛的肝糖异生能力。 | The objective of the present study was to investigate the effect of energy intake during the dry period on the expression of Pyruvate carboxylase (PC) and Phosphoenolpyrevate carboxykinase (PEPCK) mRNA in the liver of periparturient diary cows. Thirty healthy multiparous Holstein cows were randomly allocated into three groups and fed on 100% energy diet (standard diets), 120% energy diet and 80% energy diet,respectively, beginning at the 28th day before parturition. After calving, all the cows were offered the lactation ration ad libitum until the 56th day postpartum. Quantitative PCR analysis of RNA from liver biopsy samples obtained on days -28、-14、+1、+14、+28、and +56 relative to calving indicated that PC and PEPCK mRNA expression were responsive to diet. Abundance of PC mRNA was the highest in the 80% energy diet cows during experimental period. Liver PEPCK mRNA abundance increased after parturition in the low energy diet group of cows compared with the other groups of cows except a period of the first 14d postpartum. The results demonstrate that the low energy diet during the dry period could improve the liver glyconeogenesis in the periparturient diary cows.
Показать больше [+] Меньше [-]Study on integrative cultivation technology of organic rice and practice
2005
Cao Liming,Shen Guohui,Zhang Jianhan
通过筛选和搭配种植不同类型品种;应用水稻移栽前农田养草灭草,移栽后水层控草、辅以稻田养鸭,后期人工拔草补治等技术进行草害防治;与豆科作物轮作、种植根瘤菌接种的绿肥作物培肥土壤等综合技术提高有机稻米生产能力,在有机稻米生产中取得了显著成效。 | A significant progress was made in improving organic rice productiveness.The techniques are as follows:i)selecting and collocating different varieties;ii)preventing and controlling weeds through killing the growing weeds before transplanting rice and controlling weeds after transplanting rice as well as duck weeding and hand weeding;iii)improving s;Oi1 fertility by rotation with leguminous plants and inoculation with green manure crops;iv)using biological prevention and treatment.
Показать больше [+] Меньше [-]Nitrogen use efficiency and its research advances in maize
2005
Wang Jinjun, Huang Ruidong
玉米氮效率的基因型差异决定了不同氮肥供应条件下氮素吸收能力的差异,选用氮高效品种可以在低氮条件下获得高产,减少氮肥的浪费。近年来国内外对玉米氮效率的研究主要有以下几个方面:植株性状与氮效率的关系、氮效率的生理生化基础、氮效率的遗传改良等。对玉米氮效率及研究进展进行了综述,并讨论了如何继续开展对玉米氮效率的研究工作。
Показать больше [+] Меньше [-]Screening and application of fresh food and forage dual purpose broad bean varieties
2005
Wu Chunfang,Tang Yiqi,Zhang Fang
通过对不同品种蚕豆进行鲜食、饲草产量及相关性状的筛选研究,结果表明:大粒菜用蚕豆通鲜1号和通鲜2号的鲜荚、干籽、饲草综合产量高,是目前生产上鲜食饲草兼用的较为理想的品种。通过品质分析得出:①青刈蚕豆干物质中总能量和粗蛋白均比青刈苜蓿高,是很好的青刈饲草资源;②鲜食蚕豆籽,味甘鲜酥,富含营养,是重要的蔬菜作物。由此可见,它虽是小作物,却存在有潜力可挖的大市场。 | The experiments of the fresh pod yield,dry seed yield and forage yield of 9 broad bean varieties showed that Tongxian No.1 and Tongxian No.2 have higher yields of fresh pods,dry seeds and forage,and are fairly ideal varieties of the fresh food and forage dual-purpose broad bean produced at present.The results of quality analysis showed that the total energy and crude protein in the dry matter of green harvested broad bean are higher than those in the dry matter of green harvested alfalfa,and the fresh seeds of broad bean taste sweet and delicious, and are an important nourishing vegetable crop.
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