Field experiments were conducted in Cd-contaminated farmland in T and Y locations of northwest Guizhou.Twenty one common potato varieties in northwest Guizhou were used as research objects to analyze the effect of varieties and environment,and to explore the Cd absorption characteristics and edible safety of different varieties of potato tubers,in order to provide practical reference for the safe planting of potatoes in northwest Guizhou.The results showed that the yield of different potato varieties in Y location ranged from 3 564.3 kg/ha to 15 271.8 kg/ha,with an average of 9 200.1 kg/ha.The yield o different potato varieties in T location ranged from 1 825.9 kg/ha to 16 305.6 kg/ha,with an average o6 754.0 kg/ha.Zhuanxinwu in T and Y locations had the highest potato tuber yield.Variety,environmen and their interaction had significant effects on potato tuber yield.The Cd content in tubers of different potato varieties in Y location ranged from 0.061 to 0.153 mg/kg,with an average of 0.094 mg/kg.The Cd content in tubers of different potato varieties in T location ranged from 0.055 to 0.111 mg/kg,with an average of 0.080 mg/kg.Variety,environment and their interaction had significant effects on Cd content in potato tubers.The standard exceeding rates of Cd in 21 potato varieties tested in Y and T locations were 38.09% and 14.29%,respectively.The Cd content in tubers of Qingshu 9 was the lowest in both Y and T.The edible safety evaluation showed that eating Cd-excessive potato varieties had less risk to human health,but considering the Cd content in tubers,it is suggested that the varieties of potato with excessive Cd content should be used as industrial raw materials more safely.

为探讨不同玉米品种籽粒镉(Cd)、砷(As)积累能力的差异及品种与环境的作用效应,并筛选出籽粒Cd、As低富集的玉米品种,以毕节市七星关区50个当地种植的玉米品种为材料,在七星关区T地与Y地的Cd、As污染耕地采用田间小区试验对玉米籽粒Cd、As积累差异进行研究.结果表明,品种、环境及品种与环境互作对玉米籽粒Cd、As含量均有极显著影响.玉米籽粒重金属含量存在较大差异,总体表现为Cd＞As.T、Y两地50个玉米品种籽粒As含量均显著低于粮食As限值(0.7 mg/kg,NY 861-2004)与饲料As限值(2.0 mg/kg,GB 13078-2017);T、Y两地50个玉米品种籽粒Cd含量均显著低于饲料Cd限值(1.0mg/kg,GB 13078-2017);T、Y两地种植的新中玉801、金都玉2号、金都玉808、康农玉109、铜玉3号与渝单7号6个品种较稳定,其Cd含量均高于粮食Cd限值(0.05 mg/kg,NY 861-2004),此外,在T地,金湘369 Cd含量也高于粮食Cd限值(0.05 mg/kg,NY 861-2004).综上,在研究区Cd、As污染耕地上,50份玉米种质均可作为饲料原料种植;新中玉801、金都玉2号、金都玉808、康农玉109、铜玉3号、渝单7号与金湘369不可作为粮食种植,其余玉米品种可作为粮食种植.

本文通过分析七星关区农村沼气的发展现状和特点，指出了农村沼气建设取得的经济、社会和生态的显著效益，同时针对农村沼气发展中出现的认识、发展思路、融资机制、管理服务等方面的制约因素，提出了相应的对策和建议。

毕节市七星关区农作物秸秆资源丰富，秸秆的综合利用关系着全区资源开发、环境保护、农业发展和新农村建设。本文简述了七星关区农作物秸秆综合利用的现状，分析了其存在的问题，提出了推进全区农作物秸秆综合利用的对策。

通过施用沼肥对白菜产量的影响试验,结果表明,施用沼肥能促进白菜生长,使白菜叶片肉质增厚,增产效果明显,以基施沼肥4.5万kg/hm2,在幼苗期、莲座期、结球初期、结球中期分别用50%沼液喷施1次,结球初期、结球中期分别加施尿素75 kg/hm2的最好,白菜净重达58 266.7 kg/hm2.用沼肥代替部分化肥,不仅可以提高经济效益,同时可减轻大量或不合理使用化肥带来的环境污染等问题,以改善土壤生态条件,白菜病害发生轻,有利于无公害生产.

为探索玉米沼肥营养坨育苗对玉米产量的影响,进行了玉米沼肥营养坨育苗试验.土壤与肥料分别按3:1(CK)、2:1、1:1、1:2、1:3的比饲配制营养土(体积比),结果表明,加大营养土中的沼肥用量,可不同程度地提高作物产量,其中以1:1比例配制营养土育苗单位产量曩高(693.36kg/667m2),较对照增产9.04%.

沼肥中含有丰富的有机质、腐殖酸及氮、磷、钾、钠、钙等多种营养元素,为提高毕节市水稻生产上应用沼肥的水平,促进粮食增收,于2005年进行了试验.

随着沼气池建设的发展,不断推广"三沼"综合利用,提高沼气建设的综合效益成为当前沼气建设的重要课题.为此,在上级部门的支持下,我们于2005年开展了沼肥在水稻上应用试验,结果如下:

毕节市自2001年开始实施沼气工程以来,至今已发展沼气池6000余口.为进一步提高沼肥在水稻生产上的应用水平,促进粮食增产.2005年特开展本试验.