不同施氮量对烤烟生产的影响

通过田间小区试验,研究了施氮量对烤烟产量、品质和效益的影响。结果表明,在施氮量为22．5－67．5kg／hm2范围内,随着施氮量的增加,烤烟产量、效益提高,评吸鉴定品质提高。当施氮量过多时,产量增加,但品质和效益降低。施氮量37．5kg／hm2时,烤烟产值达到最高,品质最佳     

摩尔法测定烟叶氯含量的前处理方法改进初探

根据氯元素在烤烟烟叶中的存在形态,对常规测定方法的前处理方法进行了改进,通过试验发现:当烟叶样品质量不超过0.500 0 g时,以25 mL 0.2 mol.L-1 H2SO4溶液在25℃对烟叶浸提20 min,同时添加与样品质量相当的活性炭对其脱色,可以得到透明清澈的待测液。该方法的氯元素回收率为101.4%～102.6%,准确度符合测定要求,与常规方法相比,不仅测定用时短、操作简便,还可明显节约费用,便于普及应用。     

Vavilov wheat accessions provide useful sources of resistance to tan spot (syn. yellow spot) of wheat

Host genetic resistance is the most effective and sustainable means of managing tan spot or yellow spot of wheat. The disease is becoming increasingly problematic due to the adoption of minimum tillage practices, evolution of effector‐mediated pathogenicity, and widespread cultivation of susceptible cultivars from a narrow genetic base. This highlights the importance of broadening the diversity of resistance factors in modern breeding germplasm. This study explored 300 genetically diverse wheat accessions, originally sourced from the N. I. Vavilov Institute of Plant Genetic Resources (VIR), St Petersburg, Russia. The collection was screened for resistance to tan spot at seedling and adult stage under controlled conditions, and in the field across 2 years. The phenotypic datasets, coupled with ToxA bioassay screening, identified a number of accessions with useful sources of resistance. Seedling disease response corresponded well with ToxA sensitivity (r = 0.49, P < 0.000), but not adult responses (r = ?0.02 to ?0.19, P < 0.002), and overall reactions to ToxA appeared to show poor correspondence with disease response at the adult stage. ToxA‐insensitive accessions were generally found resistant across different growth stages (all‐stage resistance, ASR) in all experiments (seedling and adult stage under controlled conditions and field). ToxA‐sensitive accessions that were susceptible at seedling stage, but resistant at both adult‐plant stages, were deemed to carry adult‐plant resistance (APR). This study provides detailed information on the degree of tan spot resistance in the Vavilov wheat collection and discusses strategies to harness these sources to boost the diversity of resistance factors in modern wheat breeding germplasm.     

新色型突变棕色貉毛色遗传初探

2006年首次发现新色型突变棕色貉,近3年内累计扩繁89只。依据孟德尔遗传定律,对不同选配组合后代毛色分离数据的统计分析和x^2适合性检验证明,其突变棕色毛色基因为显性,基因型为杂合体。建议其基因符号用“G”表示,基因型为“Gg”。     

含水率对稻米籽粒剪切特性的影响研究

稻米籽粒的剪切特性指标可以作为稻米品质评价的指标之一,本文通过试验获得了稻米籽粒剪切特性的力学指标包括硬度、破坏能、破坏力及破坏应力等,并研究了含水率对稻米籽粒剪切特性的影响,通过多项式回归建立了剪切特性指标与含水率之间关系的回归方程,为水稻品质育种,评定和控制水稻的最后质量提供新的方法和新的研究手段.     

牡丹红斑病的研究

牡丹红斑病在山东菏泽牡丹栽培区的发病率达50％左右,病重的牡丹园可达90％以上。从8批次384个样品中分离获得512个分离株,经筛选、纯化、回接试验,依其培养性状和形态特征,病原菌鉴定为牡丹枝孢Cladosporium paeoniae Pass。病害发生与牡丹不同品种、初侵染源等因子密切相关。筛选出了50％多菌灵、70％甲基托布津等防治红斑病的有效药剂,应用800倍液从3月中旬牡丹展叶前至7月中旬防治4次,效果达90％以上,感病指数可控制在5以下。     

常规优质稻品种比较试验

为筛选适宜宁化县种植的高产、优质、高效的常规稻优良品种,引进5个常规优质稻品种与当地种植面积较大的5个杂优品种进行品比试验,以谷优929作对照品种,结果表明：金农丝苗、合美占、合丰占3个品种的产量与对照品种差异不显著,综合表现较好,可进一步试种.     

湘中地区烟草中拟除虫菊酯类农药残留现状与评价

按照烟草行业标准方法,湖南省湘中地区6个县市的12个X2F等级的烟叶样品的氟氯氰菊酯、氯氰菊酯、氰戊菊酯、溴氰菊酯等4种拟除虫菊酯类农残进行检测,并利用CORESTA农残限量对检测结果进行评价。结果表明,烟叶中主要是检测出氯氰菊酯（0．147～0．758mg／kg）和氰戊菊酯（0．264～0．930mg／kg）的残留,氟氯氰菊酯和溴氰菊酯均未检出,符合CORESTA农残限量标准。     

几种生物农药对青海蚕豆主要病虫害的防治效果

为建立蚕豆病虫害全程生物防控技术,以推动青海有机蚕豆生产,本研究以9种生物农药为供试药剂,针对苜蓿蚜、蚕豆赤斑病及枯萎病,开展了较为系统的室内生物活性测定和田间药效试验。室内生测试验表明,0.3%苦参碱水剂等4种生物农药均对苜蓿蚜有良好的毒杀作用,其中0.3%苦参碱水剂的毒力最强,其24h和48h的LC₅₀分别为7.33mg/L和5.66mg/L;田间防效试验表明,0.3%苦参碱水剂和0.5%藜芦碱可溶性液剂对苜蓿蚜的防效显著,500倍药液药后7d防效达76.00%～83.00%;10%小檗碱可湿性粉剂和枯草芽胞杆菌（1000亿芽胞/g）可湿性粉剂混用对蚕豆赤斑病的防效有增效作用,制剂用量为500.0g/hm²时,药后14d防效为73.98%～77.79%;多粘类芽胞杆菌（10亿CFU/g）可湿性粉剂和哈茨木霉（≥2亿活孢子/g）可湿性粉剂对蚕豆枯萎病的防效高于另两种生物农药,药后14d防效分别为74.23%和71.01%。综上所述,0.3%苦参碱水剂、0.5%藜芦碱可溶性液剂、10%小檗碱可湿性粉剂、枯草芽胞杆菌可湿性粉剂、多粘类芽胞杆菌可湿性粉剂和哈茨木霉可湿性粉剂对蚕豆3种主要病虫害防效优良,据此可进一步建立蚕豆病虫害全程生物防控技术用于青海蚕豆的有机绿色安全生产。     

关于桐梓县提升烟叶收购站点规范管理的几点思考

为探索烟叶收购站点规范管理的可行路径和有效措施,通过走访调研,广泛听取烟草公司干部职工代表、烟农代表、合作社相关人员的意见,全面掌握了当前烟叶收购中存在的问题,提出烟叶收购站点规范管理“四个一”的对策建议。