Yield performance and optimal nitrogen and phosphorus application rates in wheat and faba bean intercropping

Yield performance in cereal and legume intercropping is related to nutrient management, however, the yield response of companion crops to nitrogen (N) input is inconclusive and only limited efforts have focused on rationed phosphorous (P) fertilization. In this study, two multi-year field experiments were implemented from 2014–2019 under identical conditions. Two factors in a randomized complete block design were adopted in both experiments. In field experiment 1, the two factors included three planting patterns (mono-cropped wheat (MW), mono-cropped faba bean (MF), and wheat and faba bean intercropping (W//F)) and four N application rates (N0, 0 kg N ha^–1; N1, 90 and 45 kg N ha^–1 for wheat and faba beans, respectively; N2, 180 and 90 kg N ha^–1 for wheat and faba beans, respectively; and N3, 270 and 135 kg N ha^–1 for wheat and faba beans, respectively). In field experiment 2, the two factors included three P application rates (P0, 0 kg P₂O₅ ha^–1; P1, 45 kg P₂O₅ ha^–1; and P2, 90 kg P₂O₅ ha^–1) and the same three planting patterns (MW, MF, and W//F). The yield performances of inter- and mono-cropped wheat and faba beans under different N and P application rates were analyzed and the optimal N and P rates for intercropped wheat (IW) and MW were estimated. The results revealed that intercropping favored wheat yield and was adverse to faba bean yield. Wheat yield increased by 18–26%, but faba bean yield decreased by 5–21% in W//F compared to MW and MF, respectively. The stimulated IW yield drove the yield advantage in W//F with an average land equivalent ratio (LER) of 1.12. N and P fertilization benefited IW yield, but reduced intercropped faba bean (IF) yield. Nevertheless, the partial LER of wheat (pLER_wheat) decreased with increasing N application rates, and the partial LER of faba bean (pLER_{faba bean}) decreased with increasing P application rates. Thus, LER decreased as N input increased and tended to decline as P rates increased. IW maintained a similar yield as MW, even under reduced 40–50% N fertilizer and 30–40% P fertilizer conditions. The estimated optimum N application rates for IW and MW were 150 and 168 kg ha^–1, respectively, and 63 and 62 kg ha^–1 for P₂O₅, respectively. In conclusion, W//F exhibited yield advantages due to stimulated IW yield, but the intercropping yield benefit decreased as N and P inputs increased. Thus, it was concluded that modulated N and P rates could maximize the economic and ecological functions of intercropping. Based on the results, rates of 150 kg Nha^–1 and 60 kg P₂O₅ ha^–1 are recommended for IW production in southwestern China and places with similar conditions.     

红黑小豆杂交F3世代粒色变异和抗氧化性分析

选用红、黑2种粒色小豆材料进行杂交,研究该杂交组合F3世代籽粒色泽及总抗氧化性遗传变异。结果表明,红、黑粒色小豆杂交后代出现黑、蓝黑、花斑、黄白、黑红、浅红和红等多种色泽类型。F3世代籽粒在L*、a*和b*3个色泽参数上存在较大变异,L*和b*值出现超高亲材料。以植株为单位的籽粒总抗氧化能力测定值存在明显超亲现象,最高值(2.048U/mg)比高亲值(1.439U/mg)提高42.52%。相关分析表明,总抗氧化能力测定值与色泽参数a*呈极显著负相关,对于小豆红-绿类型高总抗氧化材料的选择具有参考价值。     

辽宁省大豆更替品种主要农艺性状研究

本文研究了建国以来辽宁省大豆更替品种主要农艺性状的遗传改进及主要农艺性状与更替品种产量的关系。总的趋势是13个性状中除了分枝数以外其余性状均有不同程度的增长，其中三粒英数、分枝英数、单株粒重、粒茎比、株高及主茎节数的增长量较大，生育期变化量最小。相关与通径分析结果表明，单株粒重与单株荚数、主茎荚数、分枝荚数、百粒重和粒茎比有直接相关效应。单株荚数对单株产量的直接效应最大，是影响单株产量的主要因子。     

缺硼对绿豆叶片光合特性和碳水化合物含量的影响

本试验以绿豆为指示植物,采用溶液培养法研究了缺硼对叶片光合功能和碳水化合物含量的影响,以明确缺硼是否影响光合作用进而影响作物生长。在绿豆第二片真叶出现后的第二天,一半植株供给 50 mol/L 硼（高硼）,另一半植株供给0.2 mol/L 硼（低硼）,在叶片生长过程中动态监测叶绿素含量、 气体交换和碳水化合物含量。结果表明,缺硼对叶片叶绿素含量没有影响,缺硼降低了光合速率（Pn）和气孔导度（Gs）,但对胞间二氧化碳浓度（Ci）没有影响; 缺硼提高了气孔限制率（Ls）。虽缺硼降低了Pn,但提高了叶片中可溶性糖,特别是葡萄糖和淀粉的含量。本研究结果表明缺硼对植物生长的影响并非是由于碳水化合物缺乏的缘故,而是因降低库活力导致了Pn的降低。     

薇菜试管苗移栽试验

通过对薇菜试管苗进行不同等级、不同移栽基质移栽试验,研究薇菜试管苗的最适移栽时期、最适移栽基质。试验结果表明：用遮阳网＋微膜覆盖保湿,在保持温度20～28℃,湿度90%～100%,散射光照条件下以合格单株定植于椰茸中成活率高达97.6%。     

几个玉米品种对比试验研究

为了配合种植业调整、稳定提高农业经济效益,筛选适合当地栽培的优良玉米品种。采用了8个优质玉米杂交品种,以绥玉7号为对照,进行适应性、丰产性及抗逆性等对比试验,试验结果表明龙单29综合经济性状表现突出,产量显著高于对照,且茎秆粗壮,成熟度较好。     

基于SSR小豆新品种(系)DNA指纹图谱构建及亲缘分类初探

为寻求鉴定小豆品种基因型的新途径,对不同地区来源的37个新品种(系)和12个品种资源进行了SSR分析。利用7对SSR引物扩增出的22个多态位点,对供试品种(系)进行了区分,初步构建出供试品种(系)DNA指纹图谱。聚类分析表明,当截值取0.37时,49个小豆材料可划分为7个类群。37个育成品种(系)全部聚在同一类群内,遗传差异相对较小;在育成品种类群内,可划分为8个具有不同特征的亚类群,聚类结果与品种(系)的系谱来源相吻合。地方品种资源内的遗传多样性较高,与育成品种间遗传距离较远。     

山东主要水稻品种演变及系谱分析

50多年来,山东省水稻品种经过4次大的更新,每一次更新都对稻作起到了极大的促进作用。山东水稻品种选育中,桂花黄、日本品种以及地方品种对水稻品种改良起到了关键作用。山东省水稻育种工作还应加大国内外优良稻种资源的引进和利用,并注重应用育种新技术和新方法。     

科研单位新品种保护动力不足的成因分析

文章针对我国农业科研单位新品种保护不到位的现象,分析了制约新品种保护的问题和成因,提出了加强农业科研单位植物新品种保护的对策与措施。     

甘蔗新品种综合性状的灰色关联度分析

采用灰色关联度分析法,对江西省6个甘蔗新品种的综合性状进行了评估。分析结果表明,赣南02／302和赣南02／287综合性状最优良;赣南99／591、赣南02／70接近对照,也是优良品种;赣南02／296、赣南02／298的综合性状较差。