12月龄雷琼黄牛生长曲线拟合的比较分析

为研究雷琼黄牛的早期生长发育规律,试验测量了300头不同月龄雷琼黄牛的体重和体高等生长指标,以SPSS 21.0软件进行相关性分析,再分别利用Brody、Von Bertalanffy、Logistic和Gompertz四个模型对试验牛的体高、胸围、体斜长和体重进行了拟合分析.结果表明:12月龄雷琼黄牛体高(x2)、腹...     

欧美杨类杨树速生性状早期预测的研究

本文调查了遗传上相似的10个欧美杨类无性系一年生扦插苗年生长季节变化规律,测定了与生长相关的一些生理生化及叶形态指标。单株叶面积、硝酸还原酶活性、过氧化物酶活性、速生期、干物质在茎的分配百分率与11年生材积紧密相关(r=0.602～0.908),能分别作为速生性状早期预测的单一指标。以样本主成分值与11年生材积建立的多元回归模型,相关系数达到极显著水平。     

犊牛开食料的研制及其犊牛生长发育规律的研究(一)

本次试验用我们所研制的犊牛开食料进行了犊牛早期断奶,并对犊牛生长发育进行了对比试验研究。将黑白花犊牛分为试验组(早期断奶组)和对照组(常规断奶组)。试验组哺乳期为10～42日龄,育成期为43～91日龄。对照组哺乳期为10～91日龄。两组观察期为92～182日龄。犊牛开食料的干物质含量为91.6％、粗蛋白质为20.52％、粗纤维为3.87％。在10～42日龄时平均日增重试验组为606.77g、对照组为518.49g,两组间差异显著(P<0.05);在43～91日龄时平均日增重试验组为1019.78g。对照组为821.09g,组间差异显著(P<0.05);在整个试验期(10～91日龄)的日增重试验组均高于对照组,差异显著(P<0.05)。体尺各部位增长试验组均高于对照组,尤其是腹围增长较快,10～42日龄时组间差异显著(P<0.05),可见早期断奶犊牛反刍胃的发育得到了明显提前。182日龄时,试验组体重为204.5kg、对照组为199.0kg,两组牛平均日增重较接近,差异不显著(P>0.05)。     

PP333对密植桃树早实丰产作用的研究

在１×１×１．５ｍ的密植桃园（５３４株／亩）定植春蕾和无核早二品种半成苗，于当年生长期和落叶休眠期，用不同剂量ＰＰ３３３（０．１５，０．３０，０．４５，０．６０ｇ／株）进行土壤施入。ＰＰ３３３具有控制树冠、促进成花、降低节间长度和成花始节位、增大根冠比、加大木质部导管密度和粗度、改善地上部营养和水分状况等作用，早实丰产效果明显．     

施氮量与栽插苗数对杂交早稻“鄱优364”产量的影响

为探明施氮量和栽插苗数对新型杂交早稻新品种"鄱优364"产量形成的影响,在16.67 cm×20 cm同一栽插规格下,探讨其不同施氮量(0,120,150,180,210 kg/hm25个水平)和栽插苗数(2,3,4根/穴3个水平)下产量及其构成等指标的差异性。结果表明:施氮量对产量、有效穗数、每穗粒数、结实率和千粒质量具有极显著影响,纯氮为210 kg/hm2时,增穗、增产效果均不明显,反而降低了每穗粒数和结实率;随着栽插苗数增加,产量和有效穗数也随之增加,每穗粒数随之降低,结实率和千粒质量呈降低趋势;施氮量和栽插苗数互作对产量、每穗粒数、结实率和千粒质量有极显著影响,随着施氮量和栽插苗数的增加,产量增加,然而每穗粒数、结实率和千粒质量随着施氮量和栽插苗数的增加而减少,对有效穗数无显著影响。施氮量180 kg/hm2结合栽插苗数4根/穴有利于"鄱优364"增产。     

马铃薯早疫病拮抗菌株筛选及其抗菌活性

为更加有效地利用微生物资源控制马铃薯早疫病,采用平板对峙法,筛选马铃薯早疫病病原菌的拮抗菌株,通过含毒介质法探究拮抗菌株的抗菌活性。结果表明:44个供试内生真菌和细菌的菌株中,7株细菌对马铃薯早疫病病原菌有显著的抑菌作用,其中菌株H3的拮抗能力最强,采用平板对峙法显示,菌株H3对马铃薯早疫病病原菌抑菌宽度为5.50 mm;对H3培养基类型进行筛选,含毒介质法显示LB发酵液的抑菌活性最高,16.7%的H3发酵液的抑制率为71.17%;菌株H3发酵液能导致马铃薯早疫病病原菌菌丝形态变化:菌丝顶端出现空泡状的膨大,菌丝隔间细胞变粗变短,原生质收缩。结果说明H3可以拮抗马铃薯早疫病病原菌。     

侵染早期小麦叶锈菌相关基因的筛选及表达分析

为挖掘与叶锈菌萌发及早期侵染相关的关键基因,利用PacBio SMRT和Illumina HiSeq测序技术对叶锈菌夏孢子萌发0、2、4、8、12和24 h的孢子和芽管进行转录组测序,通过全长转录本基因表达差异分析和生物信息学分析进行候选基因筛选,利用qRT-PCR技术对候选基因在不同毒力菌系与小麦的亲和/非亲和互作中的表达模式进行系统分析。结果表明:1)综合分析筛选出差异显著且功能相关的4个候选基因,其中,PTTG_1050为SNARE蛋白的编码基因,可能参与SNARE介导的囊泡运输;PTTG_4765属于ABC转运蛋白基因家族PDR亚族;PTTG_1823属于PKc_Like超基因家族;PTTG_1279为候选分泌蛋白编码基因。2)4个候选基因在侵染早期受到强烈诱导或抑制,且在亲和互作中表达量高于非亲和互作,说明其在叶锈菌的早期侵染和扩展中发挥了重要作用,可能是早期成功侵染的关键基因。     

Effect of Pot-Mat Seedling on the Quality of Machined Transplanting and Yield Formation of Super Early Rice

【Objective】Seedling raising in pot-mat tray was the key point of pot-mat seedling mechanized transplanting technology system. This technology was conducted in early rice season to study the effects of pot-mat seedling on mechanized transplanting quality and yield of super early rice.【Method】In this study, the super early rice varieties Zhongzao39 and Zhongjiazao17 were sown in pot-mat seedling tray (BT) and traditional flat tray (CK), and then the seedling emergence rate, seedling quality, root morphology and distribution, transplanting quality and yield were investigated.【Result】There were no significant differences of seedling emergence rate between pot-mat seedling and traditional flat-mat seedling. The root system of pot-mat seedling form bowl shape, and root surface area, root diameter and root volume increased compared with traditional mat seedling. 56.03% root of BT seedling was in the bottom bowl, and the upper root was 43.97%, while that of the control seedling was 37.86% at the bottom and the upper root was 62.14%. The root-cutting rate of Zhongzao 39 and Zhongjiazao 17 pot-mat seedlings were 25.06% and 14.24%, respectively, and lower than that of flat seedling. Under the same sowing, the seedling missing-transplanting rate of pot-mat seedling treatment decreased significantly, and Zhongzao39 decreased 1.67%-3.89%, Zhongjiazao17 decreased 1.66%-2.22%. Besides, the percentage of turnover seedling, floated and injured seedlings when seedling mechanized transplant decreased compared with that of the control. The plant height, and weight of leaves, stem, root, shoot and content of chlorophyll increased at 14 days after transplanting, indicating that it was helpful to promote the early emergence and rapid growth of seedlings. The grain yield of BT treatment was significantly higher than that of control, and the yield of Zhongzao 39 and Zhongjia Zao 17 increased by 6.35%-7.66% and 8.99%-10.87%, respectively. The increase in yield was mainly achieved by the increase in the number of effective panicles. The number of effective panicles treated by pot-mat seedlings machine transplanting of Zhongzao 39 and Zhongjiazao 17 increased by 2.14%-6.01% and 4.76%-6.98%, respectively.【Conclusion】Pot-mat seedling transplanting technology improved the quality of mechanical transplanting, reduced the missing-transplanting seedling rate and injury root rate of seedling. The technique could promote early emergence of tillers, increase the number of effective panicles, and achieve high yield.     

水稻的氮磷钾养分吸收特性及其与产量的关系

在田间条件下，对包括两系杂交稻在内的8个水稻品种的氮磷钾吸收特性及其与产量的关系进行了分析研究。结果表明：早稻仅在分蘖-拨节期出现一个吸氮高峰，约占总吸氮量的60%；晚稻在分蘖期和孕穗-抽穗期出现两个吸氮高峰，分别占总吸氮量的40%和24%左右。早稻吸收磷钾的高峰期可从分蘖期-直持续到抽穗期以后，而晚稻吸收磷钾的高峰期仅在分蘖期，其吸收量占全生育期吸收量的55%以上。在稻谷产量、稻草产量和干物质总积累量方面，两系杂交稻比其它品种具有明显的优势，分别高出21%，46%和32%；在这些方面晚稻比早稻具有更明显的优势，晚稻的磷钾养分（尤其是磷素）利用效率比早稻高，晚稻吸收较少的养分而生产较多的稻谷。相关分析表明，水稻各生育阶段的吸氮量与稻谷产量呈显著正相关；而中后期的磷钾吸收多为奢侈吸收，它与稻谷产量无相关性。     

不同灌溉和施肥条件对杂交早稻品质的影响

研究结果表明 :不同灌溉和施肥处理对杂交早稻稻米的糙米率、胶稠度和直链淀粉含量均无显著影响 ,但对蛋白质含量均有极显著影响 ,在水稻生育期间保持浅水层 ,在中、后期 (特别是抽穗期 )追施氮肥 ,能提高杂交早稻稻米的蛋白质含量。