地被菊花粉萌发及花粉活力的研究

用ME的盐类和维生素附加16％聚乙二醇4000(PEG4000)和15％蔗糖对野菊及新红、塞旗红、玫瑰红的花粉进行培养。结果表明，萌发率分别为80．2％、85．3％、61．3％和46．5％。PE‰对菊花萌发有明显促进作用。但庶糖的作用不能被PEG所取代。菊花花粉萌发较合适的温度为10-20℃，在4-8℃时，萌发率及速度迅速降低，35℃萌发虽快。但花粉管短且破裂。在4℃条件下花粉可贮藏4-14d。但不宜干燥贮藏。     

Mid-storage and pre-sowing seed treatments for lettuce and carrot

Mid-storage hydration-dehydration treatments with medium-vigour lettuce seed very effectively reduced physiological deterioration in storage and ultimately showed better field emergence and final yield. Soaking-drying treatment of high-vigour lettuce seed was not effective. Pre-sowing treatment of medium-vigour lettuce seed, though less effective than mid-storage treatment, gave better field performance, but high-vigour seed did not benefit from the treatment. For carrot, both mid-storage and pre-sowing seed treatments proved beneficial, with the former showing better performance than the latter. Unlike lettuce, well-preserved carrot seed responded positively to the pre-sowing treatment.     

Reproductive roles predict sexual dimorphism in internal and external morphology of lake whitefish,Coregonus clupeaformis

Abstract – The different reproductive roles of the sexes can predict the direction and magnitude of sexual dimorphism of external and internal morphology. Males should have enlarged structures that enhance the acquisition of mating opportunities, whereas females are predicted to have enlarged organs that are associated with the production of eggs. We tested these predictions in male and female lake whitefish, a species in which both sexes have similar overall body size and shape. After controlling for body size, male lake whitefish had significantly longer jaws and pectoral and pelvic fins, larger hearts, and more muscle than females. Sexual dimorphism in relative muscle mass may be one of the most fundamental morphological differences between males and females. Females had relatively heavier livers than males. Because the liver is important for the breakdown of fats and vitellogenesis, selection should favour an enlarged liver in females for the processing of energy and the production of large numbers of eggs.     

Prepenetration stages in infection of clematis by Phoma clematidina

A detailed study of conidial germination, germ-tube growth and the formation of infection structures in Phoma clematidina , the causal agent of clematis wilt, is described for two clematis varieties differing in disease resistance. On both the resistant and susceptible varieties, the fungus entered leaves and stems by direct penetration of the cuticle, often, but not always, following the formation of infection structures. More germ tubes per conidium were formed on the susceptible host, but these germ tubes were on average shorter than on the resistant host. Although germ tubes regularly entered the plant via trichomes, stomata were not found to be sites of entry. Following penetration of the cuticle of resistant plants, germ-tube growth was sometimes restricted to the subcuticular region, and halo formation occurred at the sites where penetration was attempted. Subcuticular growth and halo formation were not observed on susceptible plants. These observations may partly explain the resistance of small-flowered clematis varieties to P. clematidina .     

甘肃温室葡萄生产的能量利用与碳足迹研究

【目的】探明甘肃温室葡萄生产的能量投入和碳足迹构成,识别主要的碳排放贡献因子,为温室葡萄清洁生产提供依据。【方法】以甘肃温室葡萄为研究对象,将温室葡萄栽培区分为兰州市永登县及武威市凉州区、古浪县、天祝县华藏寺镇和天祝县哈溪镇5个不同海拔区域,通过农户调查获得2019年葡萄生产数据,核算温室葡萄生产各环节的能量输入、能量输出和碳排放,对比分析不同海拔区域温室葡萄生产的能量利用效率、能量生产率、净能量、比能和碳足迹。【结果】甘肃温室葡萄生产的能量输入为273 862～434 421 MJ/hm²,能量输出为170 723～327 962 MJ/hm²,葡萄产量为14 460～27 793 kg/hm²,属于高投入高产出型。甘肃温室葡萄生产的能量利用效率为0.45～1.13,能量生产率为0.038～0.096 kg/MJ,净能量为-263 798～2 496 MJ/hm²,比能为13.51～44.85 MJ/kg;直接能量投入和可再生能量投入占比低,间接能量投入和不可再生能量投入占比高。单位面积碳足迹和单位产量碳足迹分别为32 959～55 075 kg/hm²和1.59～5.70 kg/kg,碳足迹很大程度上来源于氮肥的投入,其占比达45.5%～62.4%。不同区域相比,天祝县哈溪镇温室葡萄生产的能量输入低,能量输出和产量较高,能量利用效率和能量生产率也较高,净能量最大且为正值,比能最小,单位面积碳足迹和单位产量碳足迹均最小;天祝县华藏寺镇能量利用指标最差,碳足迹最大。【结论】甘肃温室葡萄生产的能量利用效率较低,碳足迹较高,能量利用效率的提高和碳足迹的降低空间均较大。因此应采取降低氮肥使用量、优化氮肥与有机肥配比等科学合理的管理措施,提高甘肃温室葡萄生产的能量利用效率,降低碳足迹,改善其环境效应。     

4种外源激素处理对羊草种子萌发和幼苗生长的影响

研究了100~600μg/g赤霉素(GA3)和吲哚乙酸(IAA)、25~100μg/g 6-苄氨基嘌呤(6-BA)和脱落酸(ABA)对羊草种子萌发和幼苗生长的影响。结果表明,100~300μg/g GA3和IAA以及25μg/g 6-BA对羊草种子的萌发最终表现为促进作用,总体效果为GA3>IAA>6-BA。当GA3和IAA浓度大于400μg/g或6-BA浓度大于50μg/g时对羊草种子的最终发芽率均表现为不同程度的抑制;25~100μg/g的外源激素ABA对羊草种子萌发没有抑制作用。GA3处理均能显著促进羊草幼苗的伸长,IAA和6-BA则表现为不同程度的抑制作用;GA3、IAA和6-BA 3种促进激素对羊草的根长和根冠比均表现为抑制作用;25~100μg/g ABA对羊草苗长、根长以及根冠比没有显著影响。     

油菜菌核病菌的生物学特性研究

在不同温度、不同ｐＨ值的ＰＤＡ平板上培养油菜菌核病菌核和菌丝块,观察菌核萌发的最适温度和菌丝生长的最适温度、最适ｐＨ值,结果表明菌核萌发的最适温度为２４～２８℃,菌丝生长的最适温度为２０～２８℃,３５℃为菌丝的致死温度,菌丝生长的最适ｐＨ值为４.７～８.５。     

北疆“一年两作”冬小麦-复播青贮玉米模式物质生产及资源利用率研究

为建立与农区畜牧业发展相适应的资源高效利用的新型饲料生产体系,满足市场对青贮玉米需求,2011—2012年在新疆天山以北地区对冬小麦-复播青贮玉米、单季冬小麦、单季青贮玉米不同模式的物质积累和生育过程的光、温资源的实际利用效率进行系统测定分析。结果表明,冬小麦-复播青贮玉米双季模式优于传统单季种植冬小麦模式,其全年干物质生产率提高84.8%、周年干物质产能提高87.8%,年总辐射利用效率提高87%,年总有效积温利用率103%。复播青贮玉米干物质生产效比春播率低7.1%,太阳总辐射生产率和温度生产效率复播比春播分别高0.12 g·J^-1和0.7 kg·hm^-2·℃^-1。因此冬小麦-复播青贮玉米具有高产高效特点,为一熟 农区畜牧发展提了一条新型饲料生产种植模式。     

环境因素对芸苔链格孢生长发育的影响

研究结果表明,芸苔链格孢(Alternaria brassicae)在0—35℃下均可萌发,最适温度15—20℃。菌丝在0—30℃下均能生长,最适温度20—25℃;孢子及菌丝的致死温度为50℃,10分钟。该菌对湿度要求较严格,相对湿度在90％以上时孢子才能萌发,最适相对湿度为98％;病菌在相对湿度达93％时可以侵染,98％以上最适。脱落后孢子曝露在室内(相对湿度约63％)经1小时萌发率下降32.4％,4小时下降80％。耐旱能力较差。一般情况下紫外光能促进该菌产孢,但是对某些菌系的促进作用不明显。过长的紫外光照射对该菌产孢不利,照射160分钟孢子萌发率下降近80％。麦芽糖、蔗糖为该菌的最佳碳源;硝态氮、有机氮是该菌的良好氮源。pH值为4—6时有利于分生孢子萌发,强酸、强碱对分生孢子萌发有抑制作用。     

玉米丝黑穗病原菌冬孢子萌发条件研究

通过不同条件对玉米丝黑穗病菌冬孢子萌发率影响的试验研究表明,甲醛处理对玉米丝黑穗病菌冬孢子萌发有明显促进作用,萌发率达88.89%,冬孢子在麦芽糖和水琼脂培养基上萌发率最高达84.49%。在不同温度和pH条件下冬孢子萌发率差异较大。冬孢子在28℃时最适合萌发,达89.67%,在pH为7时萌发率最高达89.02%。