光周期对异色瓢虫卵巢和脂肪体发育的影响

为探究光周期在异色瓢虫雌虫卵巢和脂肪体发育过程中的作用以及明确二者之间关系,研究了20℃条件下异色瓢虫雌虫在13个光周期组合下卵巢和脂肪体发育情况,结果表明:在光照时间多于14h(包括14h)时,76%以上的雌虫卵巢发育集中在Ⅳ级、Ⅴ级,全部脂肪体发育为1级或2级,此时卵巢管长度为962.42~1 095.76μm,显著长于短光照下的卵巢管长度;在光周期为10L∶14D时,94.12%雌虫卵巢发育为Ⅰ级、Ⅱ级,卵巢管长度最短,为213.33μm,88.2%的脂肪体发育等级为3级,脂肪体发育水平最高;在光周期为2L∶22D、4L∶20D、6L∶18D、8L∶16D、12L∶12D时,卵巢的5个发育等级同时出现,且发育为Ⅲ级的个体占到了总体的40%;卡方检验显示,异色瓢虫雌虫卵巢与脂肪体发育呈负相关。     

一种潜在的褐飞虱生防真菌:桔形被毛孢的分离、鉴定与培养

分离、鉴定与培养了一种自然侵染褐飞虱的病原真菌,为褐飞虱生物防治提供科学依据。通过对病原真菌的形态和培养特征的观察,鉴定该菌种为桔形被毛孢(Hirsutella citriformis Speare)。该菌是中国的新记录种。该菌孢梗束从被感染的寄主各部分伸出,长7 mm,直径83.2~156.0μm。瓶梗基部椭圆形,(5.2~7.8)μm×(2.6~5.2)μm,向上突然变细呈长管状,(28.6~32.5)μm×(0.7~0.9)μm;分生孢子,无隔,纺锤形,(6.5～5.2)μm×(1.3~2.6)μm。在室内进行的温度和光周期对该菌生长的影响表明,该菌在15~30℃均可生长,最适生长温度25℃。全明和全暗两种光周期对菌落生长影响不显著。     

Eco-physiological studies on desert plants: germination of Halothamnus iraqensis Botsch. seeds under different conditions

With the aim to investigate if the halophyte Halothamnus iraqensis Botsch. can be suitable for re-vegetation and remediation of salt-affected lands, this study evaluated(1) the effects of photoperiod, thermoperiod, storage period and wings' presence on its seed germination, and(2) the ability of its seeds to have successful germination recovery after salt stress. Germination tests in different photoperiods(12 h light/12 h darkness and total darkness) and thermoperiods(15℃/20℃ and 20℃/25℃) were conducted for seeds collected in 2012, 2013, 2014, 2015 and 2016. The seeds collected in 2016 were sown under different salinity levels(0, 100, 200, 400 and 600 m M Na Cl) to assess the salinity tolerance during the germination. Wings' presence highly inhibited seed germination of this species in both photoperiods and thermoperiods under all salinity level treatments. In addition, the germination recovery occurred well when seeds were deprived of their wings. The photoperiod of 12 h light/12 h darkness and the thermoperiod of 15℃/20℃ were the best conditions for seed germination. Germination percentages of H. iraqensis seeds decreased with the increasing storage duration, especially after three years of the collection. In addition, H. iraqensis seeds were able to germinate under different salinity levels, and their germination percentages decreased with increasing salinity levels. H. iraqensis seeds have the ability to recover their germination after alleviating the salt stress, irrespective of photoperiod, highlighting the halophilous character of this species.     

Effects of hypothalamic dopamine (DA) on salsolinol (SAL)‐induced prolactin (PRL) secretion in male goats

The aim of the present study was to clarify the effects of hypothalamic dopamine (DA) on salsolinol (SAL)‐induced prolactin (PRL) release in goats. The PRL‐releasing response to an intravenous (i.v.) injection of SAL was examined after treatment with augmentation of central DA using carbidopa (carbi) and L‐dopa in male goats under 8‐h (8 h light, 16 h dark) or 16‐h (16 h light, 8 h dark) photoperiod conditions. The carbi and L‐dopa treatments reduced basal PRL concentrations in the 16‐h photoperiod group (P < 0.05), while a reduction was not observed in the 8‐h photoperiod group. The mean basal plasma PRL concentration in the control group for the 8‐h photoperiod was lower than that for the 16‐h photoperiod (P < 0.05). SAL significantly stimulated the release of PRL promptly after the injection in both the 8‐ and 16‐h photoperiod groups (P < 0.05). PRL‐releasing responses for the 16‐h photoperiod were greater than those for the 8‐h photoperiod (P < 0.05). The carbi and L‐dopa treatments blunted SAL‐induced PRL release in both the 8‐ and 16‐h photoperiods (P < 0.05). These results indicate that hypothalamic DA blunts the SAL‐induced release of PRL in male goats, regardless of the photoperiod, which suggests that both SAL and DA are involved in regulating the secretion of PRL in goats.     

光周期对黄金鲈鱼生长的影响

在16L：8D和自然光N（Amb）两种光周期条件下养殖黄金鲈鱼，观察其体重增长及饲料转化情况。养殖试验结果发现经过5个月的饲养，黄金鲈鱼在16L：8D的光周期下鱼体总重量的净增量是自然光周期下的2．90倍，饵料系数比自然光照条件下低54．8％。结果表明适当延长光照时间可以促进黄金鲈鱼的生长，降低饵料系数。     

对北方粳稻杂种优势利用若干问题的讨论

从我国杂交水稻的推广、杂种优势的普遍性、籼粳亚间杂种优势利用、光(温)敏雄性不育性、广亲和基因的利用价值等方面讨论了北方粳稻杂种优势利用的现状与问题;认为从物质积累与能量转化角度探索超高产的可行途径是今后杂交水稻和常规水稻育种研究的共同课题。     

不同生态型大蒜品种生态特性研究Ⅰ．温度和光周期对大蒜鳞茎形成发育的影响

采用蒜种播前温度处理和鳞芽分化发育期光周期处理法，研究了３个大蒜生态型的３０个品种在北纬３４°１８＇地区秋播时鳞茎的形成及发育状态。结果表明，低温反应敏感型品种在１２ｈ日长下鳞茎发育良好；蒜种播前用３５℃处理４０ｄ，效果较好。低温反应中间型品种在中纬度地区自然日长下鳞茎发育良好；蒜种播前用３５℃处理４０ｄ可增加鳞茎重量。低温反应迟纯型品种在１２ｈ日长下一般不形成鳞茎，日长达１６ｈ虽可形成鳞茎但发育不良；蒜种播前用５℃处理４０ｄ对鳞茎发育有促进作用。     

芥菜和甘蓝启动抽薹的温光诱导体系研究

通过温度（x1）、光周期（x2）、处理时间（x3）三因素的二次正交旋转设计,对“大青叶”芥菜（GN）和“早秋”甘蓝（ZQ）抽薹的温光诱导体系进行筛选,分别建立了相应的回归方程,并对诱导抽薹条件进一步验证和优化,表明：在16h长日照、4℃/7℃变温下分别处理芥菜45d,处理甘蓝65d,然后转入再培养体系,均可在6d内快速启动芥菜和甘蓝100%抽薹.在启动抽薹期,芥菜和甘蓝的可溶性蛋白质和游离氨基酸含量逐渐增加,而可溶性糖和过氧化物酶呈先减后增趋势.     

大豆生态研究──Ⅵ．大豆叶片感光效应与生长发育关系的研究

叶片是感光部位。子叶和未展开叶的感光效应确定开花节位，叶片的感光效应确定生长速度。不论短光或长光叶片，均以延长开花天数中９０％的时间用于提高开花节位，以延长开花天数中１０％的时间用于增长叶龄．短光叶片生长速度全用于由于叶和未展开叶确定的开花节位，反应短光促进发育。长光叶片生长速度增长叶龄同时，提高开花节位，反应长光促进生长．叶片在扩大生长中产生的感光效应上递３节，在上递过程中发生感光效应综合平衡作用．复叶发生始到定形为展开感光效应持续期。本文还提出研究大豆光温生态的适宜光温条件。     

温度和光周期对双色泉蝇及其寄生蜂泉蝇茧蜂滞育维持和解除的影响

系统报道了在自然条件下双色泉蝇及其寄生性泉蝇茧蜂越夏代和越冬代个体的羽化情况 ,并研究了温度和光周期对两者滞育维持和解除的影响。结果表明 :(1)在自然条件下 ,双色泉蝇越夏代和越冬代全部羽化完后 ,泉蝇茧蜂才开始羽化 ,且羽化集中在一个短时间内完成 ;(2 ) 10℃低温比中性温度更有利于双色泉蝇滞育的解除 ;(3)光周期对双色泉蝇越冬蛹滞育的解除没有影响 ,但在越夏蛹滞育中短光照似乎更有利于滞育的解除 ;(4)泉蝇茧蜂的越夏滞育解除完全由光周期控制 ,在 14～ 16h的长日照下不能解除滞育 ,而在 10～ 13h短日照下全部解除滞育 ,其中在 11～ 12h光照下解除最快