苦瓜种子大小和单粒质量的遗传分析

以苦瓜自交系K7-359(P_1)和K7-422(P_2)分别作为母本和父本,通过杂交获得F_1,F_1自交获得F_2群体,采用主基因+多基因混合遗传模型分析苦瓜种子长度、宽度和单粒质量的遗传规律。结果表明,苦瓜种子长度和单粒质量的遗传均符合加性-显性-上位性多基因遗传模型(C-0模型),多基因遗传率分别为84.91%和76.55%,说明对苦瓜种子长度和单粒质量的选择宜在高世代进行;苦瓜种子宽度的遗传符合1对加性-显性主基因+加性-显性-上位性多基因模型(D-0模型),主基因和多基因遗传率分别为79.30%和3.86%,主基因遗传效应主要以加性效应为主,说明对种子宽度的改良可以采用组合育种的策略,且适宜在早期世代进行选择。     

亚精胺浸种对番茄种子萌发及幼苗高温抗性的影响

以番茄品种合作903为试验材料,设置0、0.1、0.2、0.4 mmol · L~(-1 )亚精胺(Spd)浸种10 h,研究不同浓度Spd浸种对番茄种子萌发、幼苗生长及高温抗性的影响。结果表明:不同浓度Spd浸种处理均能显著提高番茄种子的发芽指数和活力指数,幼苗地下部干质量和壮苗指数明显提高,其中0.2 mmol · L~(-1 )Spd浸种处理发芽最快,活力指数最高。Spd浸种处理降低了高温胁迫下番茄叶片的相对电解质渗透率、丙二醛(MDA)和H_2O_2含量,其中0.2 mmol · L~(-1 )Spd处理的相对电解质渗透率、MDA和H_2O_2含量最低;抗氧化酶(SOD、APX、DHAR)活性增加,并在0.2 mmol · L~(-1)时达到最大值。综上,0.2 mmol · L~(-1 )Spd浸种能有效促进番茄种子萌发和幼苗生长,提高番茄幼苗高温抗性。     

加工萝卜蜀萝9号(038A/C9274)的选育与应用

介绍了适合四川蔬菜加工的萝卜品种蜀萝9号的亲本选育经过、组合配制、品比试验、多点试验、生产试验与示范中的表现,结果表明:2年的生产示范产量可达61.02 t/hm2,比对照增产11.60%,增加经济效益显著。并对其理化品质分析的表明,蜀萝9号符合加工萝卜和企业深加工的要求,此外还提出了蜀萝9号的栽培技术与制种技术。     

外源ABA对不同品种番茄种子萌发的影响

以3种番茄种子为试验材料，研究了不同浓度ABA（0—40m/L）对番茄种子萌发的影响。结果表明，低浓度ABA（0-5mg／L）对种子的发芽势、发芽率和发芽指数没有显著影响，高浓度ABA（10-40mg／L）极显著抑制种子的发芽势、发芽率和发芽指数，且浓度越高种子萌发受到的抑制作用越强。另外，ABA推迟番茄种子的萌发，浓度越高，萌发延迟天数越多，不同番茄品种（系）对ABA浓度的敏感性不同。     

Italian ryegrass establishment by self-seeding in integrated crop-livestock systems: Effects of grazing management and crop rotation strategies

We evaluated the re-establishment of an Italian ryegrass pasture by self-seeding on a no-till integrated crop-livestock systems (ICLS) in the southern region of Brazil. This work is part of a long-term experimental protocol initiated in 2003. We tested the effects of various management practices, such as summer crop systems (soybean vs. maize–soybean rotation), stocking methods (continuous vs. rotational) and grazing intensities (low vs. moderate), on Italian ryegrass pasture establishment. In addition, we tested resilience of the system by testing pasture's ability to re-establish following a year without seed head production. The experiment consisted in the rotation, on the same area, of Italian ryegrass pasture grazed by sheep during the winter and up to the end of the grass production cycle, and soybean or soybean-maize grain crops rotation cultivated during the summer. The pasture established itself by self-seeding since 2005. Data were collected in 2011 and 2012 stocking season. The soybean summer crop, continuous stocking and low grazing intensity, all positively affected the production of reproductive tillers in 2011. Grazing intensity in 2011 strongly influenced early vegetative tiller densities (before crop harvest) in 2012. However, none of the grazing intensity or the stocking method treatments affected herbage mass at the end of pasture establishment in 2011 or 2012. On the other hand, the soybean summer crop positively affected pasture establishment, both in term of tiller densities and herbage mass at the end of pasture establishment. The removal of all seed heads in 2011 (preventing seed production) resulted in the total failure of pasture establishment in 2012. Overall, Italian ryegrass establishment by self-seeding relies on the annual replacement of the soil seed bank. This experiment demonstrated that under various stocking methods, moderate grazing intensity and maize or soybean summer crop, Italian ryegrass pasture establishment by self-seeding remains successful even when the stocking periods extended up to the end of the grass production cycle. Self-seeding with moderate grazing intensity ensures successful pasture establishment, reduces labour and costs and allows to increase the stocking period and so animal live weight gain over the grazing season.     

Movement and survival of corn rootworm in seed mixtures of SmartStax® insect-protected corn

SmartStax^® insect-protected corn (Zea mays L.) contains genes for six Bacillus thuringiensis (Bt) proteins controlling both lepidopteran pests and the corn rootworm complex (Diabrotica spp.). The properties of SmartStax, particularly the multiple effective modes of action (i.e., each Bt protein provides a high level of control of the target pests with a low probability of cross-resistance among the proteins), have provided the opportunity to add to previously approved structured refuge options by combining the non-Bt refuge seed with SmartStax seed in a seed mix. Seed mixes ensure that a refuge is present in every Bt field, remove concerns about grower compliance with refuge requirements, and provide grower convenience. However, seed mixes could increase the likelihood that larval insects move between Bt and non-Bt plants and vice versa. Assessing the insect resistance management (IRM) value of a seed mix refuge requires an assessment of the amount of larval movement, and the consequences of that movement, for the key target pests. The studies here present such data for control of corn rootworm by SmartStax corn, which contains the rootworm-active protein Cry3Bb1 and the binary protein Cry34Ab1/Cry35Ab1. In a growth chamber experiment, SmartStax was most effective against first instars and significantly effective against second instars, but did not control third instars. In a field study of movement from a heavily infested non-Bt plant onto surrounding plants, a larger percentage of insects successfully dispersed from the infested plant when the surrounding plants were non-Bt plants than when they were SmartStax plants. A paired-plant study showed that few larvae migrated from infested SmartStax plants and survived on nearby non-Bt plants; larvae that migrated from infested non-Bt plants had low survival if the adjacent plants were SmartStax. Replicated field studies of plant-to-plant movement indicated that the non-Bt plants in a 5% or 10% seed mix consistently supported large populations of susceptible insects and represented a productive refuge, whereas the SmartStax plants had few or no survivors. The timing of emergence from seed mix plots containing 5% or 10% non-Bt plants was more similar to that of the non-Bt plots than that of the SmartStax plots. Thus, the available growth chamber and field data indicate that a seed mix of 5% or more will provide an effective refuge for corn rootworm in SmartStax corn.     

播期和密度对马铃薯原种扩繁生长发育及产量的影响

在马铃薯原种生产中,播种密度和播种期对原种繁育的产量、种薯大小等有着明显的影响。选用当地主栽品种大西洋,于2017-2018年在山丹县冷凉区域,同一地点开展不同播期和密度试验。播种选择4月25日、5月5日、5月15日、5月25日和6月5日,种植密度设置60 000、90 000、120 000、150 000和180 000粒/hm ² 5个水平。结果表明,在当地的栽培模式大垄双行覆膜种植下,4月25日-5月15日播种,播种密度为120 000、150 000粒/hm ²,产量在45 285~46 770kg/hm ²,中种薯率在75.3%~79.6%,合格种薯多,均为最高,且此范围产量差异不显著。考虑到节约原原种投入降低成本,生产中优选120 000粒/hm ²的播种密度,在4月25日-5月15日种植,是大西洋原种繁育的最佳选择方案。     

不同处理方式对蔬菜种传病毒病的消毒效果评价

为了研究不同种子处理对种子传播病毒的灭活效果,试验以番茄、辣椒、甜瓜、南瓜种子样本中被番茄花叶病毒(ToMV)、烟草花叶病毒(TMV)、黄瓜花叶瓜病毒(CMV)感染的种子为研究对象,经过酶联免疫吸附测定(ELISA)和逆转录聚合酶链反应(RT-PCR)测试选择出研究材料,采用7种病毒失活处理方法,分别为醋酸、过氧化氢、盐酸、次氯酸钠浸种,干热处理,温汤浸种和臭氧熏蒸处理。结果发现,能有效减少病毒浓度的处理为盐酸浸种、干热处理、温汤浸种(65℃)和臭氧(10 g/m3)处理,分别能将种子传播病毒的浓度平均降低51%、50%、42%和32%。其他灭活方法治疗效果较差,病毒浓度平均降低了12%~27%。盐酸浸种和干热处理是最有效的方法,对种子出芽率和活力没有影响。     

重穗型两系杂交中籼新品种未两优1号的选育及应用

未两优1号是安徽未来种业有限公司选育的重穗型优质中籼杂交稻,具有熟期适中、穗大粒多、丰产性能好、生长优势强、适应性广、米质优良等特点。介绍了该组合的选育过程、品种特性、制种技术要点及高产栽培技术。     

磷肥对甘肃临夏地区燕麦干草及种子生产的影响

为确定甘肃高寒雨养区燕麦(Avena sativa)种子生产中磷肥最佳用量,提高肥料利用效率,试验在氮肥(尿素)用量75 kg·hm^-2的固定水平下,设计4个磷肥(P₂O₅)水平(0(CK),65(C₁),100(C₂),135(C₃)kg·hm^-2),对各磷肥水平下干草产量、种子产量和相关性状的变化进行了研究。结果表明：施用磷肥使燕麦的株高、茎粗、分蘖和干草产量均有提高,灌浆期C₁,C₂,C₃干草产量较CK依次提高13.85%,25.96%,22.65%,干草产量与磷肥水平显著正相关(相关系数0.91);施用磷肥提高了燕麦的有效分蘖数、主穗长,显著提高主穗粒数、穗粒重、千粒重、种子产量和秸秆产量,C₁,C₂,C₃种子产量较CK依次提高12.37%,16.72%,14.38%,种子产量与磷肥水平显著正相关...