大白菜施钾及氮钾配施效果

试验结果表明,在普施磷肥基础上,氮钾肥可明显提高产量,氮钾配施可取得最佳效益.施钾可增强大白菜的抗逆性,提高商品率,促进NO2向NO3转化,降低大白菜NO2含量.     

施钾对甜玉米产量、品质及蔗糖代谢的影响

采用田间小区试验,以甜玉米东甜3号（Dongtian3）,东甜4号（Dongtian4）为试材,研究了不同钾素用量对甜玉米产量和品质及对蔗糖代谢关键酶活性的调控作用。结果表明,施钾显著提高了甜玉米鲜穗产量,施K2O 150 kg/hm2处理比不施钾处理最高增产14.06%;各施钾处理的子粒可溶性糖、蔗糖、蛋白质、赖氨酸含量均明显提高。开花后,子粒蔗糖含量与蔗糖合成酶（SS,合成方向）和蔗糖磷酸合成酶（SPS）活性的变化规律与子粒蔗糖含量变化一致,SS和SPS活性呈显著或极显著正相关,施钾明显提高了二者活性,利于甜玉米蔗糖合成与积累。经回归分析,得甜玉米最高产量钾素用量为K2O 133 ～140 kg/hm2,最优品质的钾素用量为K2O 140 kg/hm2。     

施钾对烤烟钾素吸收利用效率及其产量和品质的影响

通过田间小区试验研究了不同施K量对烤烟K素吸收利用效率及产量和品质性状的影响.结果表明:K在烤烟各器官的累积量和含K量均表现为叶＞茎＞根,随着施K量的增加,烟叶和烟株累积量和含K量显著增加,而K肥利用率,K素干物质生产效率和K素利用效率显著下降.烟叶产量和外在品质在施K量0～315kg/hm2范围内均随施K量的增加而提高,超过315kg/hm2则下降明显.增施K肥显著提高烟叶含K量、还原糖含量,降低总N、Ca、Mg、烟碱含量.相关分析表明,K素吸收利用效率与烟叶产量品质密切相关.     

施钾量和施钾时期对棉花产量及不同部位棉铃纤维品质性状的影响

在大田试验条件下,以鲁棉研28号为材料,设置两个施钾量（K2O 100和150 kg/hm2）,采用一次性基施,1/2基施、1/2花铃期追施,研究施钾量和施钾时期对棉花（Gossyium hirsutum L.）产量及不同部位棉铃纤维品质性状的影响。结果表明:与不施钾相比,施钾显著提高了籽棉产量和皮棉产量;在施钾量为K2O 150 kg/hm2的条件下,与一次性基施相比,分期施钾极显著提高了籽棉产量和皮棉产量;采用分期施钾时（1/2基施、1/2花铃期追施）,随施钾量增加,籽棉产量和皮棉产量均显著增加,单株成铃数的增加是产量提高的主要原因。结果还表明,与不施钾相比,施钾显著提高了中部及上部果枝内围果节的马克隆值,分期施用K2O 150 kg/hm2显著提高了中部果枝外围果节的纤维长度、比强度以及中部果枝内围果节的纤维成熟度;在施钾时期相同的条件下,增加施钾量对纤维长度、比强度无显著影响,在施钾量相同的条件下,与一次性基施相比,分期施钾对纤维比强度无显著影响。     

施钾对不同基因型棉花光合特性及产量和品质的影响

在田间条件下,研究了施钾对抗虫杂交棉中棉所38、抗虫棉新棉33B、常规棉中棉所12光合特性和产量及品质的影响。结果表明,与不施钾相比,不同基因型棉花施氯化钾225.kg/hm2,棉花叶面积指数(LAI),叶绿素荧光动力学参数PSⅡ最大光化学量子效率(Fv/Fm)、PSⅡ潜在光化学活性(Fv/Fo)、PSⅡ实际光化学效率(ФPSⅡ),叶片净光合速率(Pn)、气孔导度(Gs),棉花干物重及分配到生殖器官的比例,棉花总成铃数、铃重和衣分均有不同程度提高;中棉所38、新棉33B和中棉所12皮棉产量分别增加13.60%、10.66%和4.21%;棉纤维2.5%跨距长度、比强度、马克隆值和纤维整齐度等品质也得到改善。中棉所38和新棉33B比中棉所12施钾的效果更好,生产上应优先给抗虫杂交棉和抗虫棉品种施用钾肥。     

不同含钾物料对冬油菜产量及钾素吸收的效应

采用大田试验研究稻草、稻草灰、硅钙钾肥、枸溶性钾肥和氯化钾肥5种含钾物料对冬油菜产量及钾素吸收的影响。结果显示,在施钾(K_2O)120 kg/hm~2时,各含钾物料的施用均可显著增加冬油菜产量和钾素累积量,与不施钾对照相比,含钾物料处理的油菜增产率为14.5%~34.9%,地上部钾素(K)总累积量增幅为71.8%~143.0%。不同含钾物料的施用效果不同,以枸溶性钾肥效果最好,其次是稻草灰和氯化钾肥。5种含钾物料的钾素表观利用率以枸溶性钾肥、稻草灰和氯化钾处理较高,其显著高于硅钙钾肥和稻草处理。各含钾物料的施用对土壤钾素供应的影响不同,油菜收获后的土壤速效钾含量以氯化钾肥和稻草灰较高,土壤缓效钾含量则以枸溶性钾肥处理最高,均显著高于其他处理。综合结果表明,在等量钾肥投入下,稻草灰和枸溶性钾肥表现出与氯化钾肥相同的施用效果。     

灰漠土菜地速效钾含量变化及施钾效应

对石河子蔬菜所试验地１２年速效钾年平均含量进行了统计，速效钾含量在逐年下降，研究了化学钾肥的效应，施用钾肥对早期产量有显著影响。     

施钾对黄土高原旱区胡麻钾素分配利用及产量的影响

为探究黄土高原地区胡麻产量形成对钾肥高效利用下的关系,以2个当地主栽胡麻品种"陇亚11号"(V1)、"定亚23号"(V2)为供试材料,设置不施钾(K0,K₂O 0 kg hm^-2)、低钾(K1,K₂O 30 kg hm^-2)、中钾(K2,K₂O 60 kg hm^-2)与高钾(K3,K₂O 90kg hm^-2)4个钾肥水平进行大田试验,研究了不同施钾量对胡麻植株钾素积累分配转运及产量形成和钾肥高效利用的影响。结果表明,施钾后V1和V2两胡麻品种钾素积累量分别上升6.67%～16.47%和12.74%～22.12%,茎钾素转运率增加10.25%～14.23%和1.64%～10.26%,籽粒钾素分配比例上升-1.68%～4.76%和3.45%～14.51%,产量分别增加1.68%～10.72%和6.68%～17.77%;中(K2)、高钾(K3)处理的V1和V2胡麻品种茎钾素转运量上升3.15%～11.59%和8.62%...     

施钾对加工番茄产量与品质的影响

通过2年的加工番茄钾肥用量田间试验和示范,研究加工番茄的钾肥效应。结果表明,施用钾肥可以显著增加加工番茄产量,经济效益显著;由钾肥的效应方程可以得出:推荐施钾(K2O)量为144~146 kg/hm2,N∶K2O为1∶0.8。施钾可以显著降低番茄果实硝酸盐含量,提高加工番茄果实茄红素含量,减少烂果量,同时可提高果实糖酸比、果实Vc和可溶性固形物含量,从而改善加工番茄品质。     

Effects of Application of Boron on Growth,Yields, and Quality of Red Bayberry

ABSTRACT

Three field experiments at three sites in east Zhejiang Province were conducted to determine the influence of applications of boron (B) on growth, yield, and quality of the red bayberry trees (Myrica rubra Sieb. et Zuca) with a manure species of “Buqizhong” in Linhai city. Ground B application or foliar B spraying significantly improved length and incidence rates of spring and summer shoots and increased fruit set rates, which resulted in the increases in fruit yield (13.7–17.5% for ground B application or 13.2–27.3% for foliar B spraying) and in improvement of fruit quality. The optimum yields were recorded with the treatments of ground B application of 40 g tree^?1 of borax or foliar B spraying of 2.0 g L^?1 of borax. Spring shoot incidents for the treatment of ground application of 50 g borax tree^?1 every year during the experiment (4B₅₀) were significantly higher than that for the treatment of ground application of 50 g borax tree^?1 only in the first year of the experiment (B₅₀), but the yield difference between them was not significant at P = 0.05. The increased yield effect of ground B application could last for 3 years. Boron application of red bayberry trees can be carried out by foliar-spraying 2.0 g borax L^?1 every year or ground application of 50 g borax tree^?1 every 3 years. The results of this study showed that application B could significantly improve the growth and increased fruit yield and quality of the red bayberry trees not exhibiting any vegetative symptoms of B deficiency.     

NUTRITIONAL DIAGNOSIS AND CORRECTION OF SHOOT DIEBACK OF RED BAYBERRY (MYRICA RUBRA SIEB. ET ZUCA)

Shoot dieback characterized by leaflet, rosette shoots, and dieback of shoot tips is one of the most important problems in red bayberry production in south China. However, the causes of shoot dieback have not been determined. The results of leaf analysis and correction experiment showed that leaf boron (B) concentrations were highly correlated with leaf area (P < 0.01), spring shoot length (P < 0.01), and spring shoot numbers sprouting from one old shoot (P < 0.05). Foliar application of B at 2.0 g L^–1 of borax was more effective on correcting shoot dieback than foliar application of Zn at 2.0 g L^–1 of zinc sulfate and of molybdenum (Mo) at 2.0 g L^–1 of ammonium molybdate. Boron application increased fruit yields by 1.23–2.15 times compared with the control. Shoot dieback resulted mainly from B deficiency in the red bayberry trees.     

Effects of Boron and Paclobutrazol on Growth,Fruit Set,Nutrient Uptake,and Alternate Bearing of Muye Red Bayberry

Alternate bearing, resulting mainly from boron (B) deficiency, and excessive fruits in the alternate years of red bayberry trees are the most important limiting factors for production. This investigation was conducted on 18-year-old Muye red bayberry trees (Myrica rubra Sieb. et Zuca) in a commercial red bayberry orchard located in Laxi County, Zhejiang Province in 2006–2007.The results indicated that foliar application of paclobutrazol (PB) significantly increased the vegetative growth parameters (i.e., spring shoot incident and spring shoot length). Spring shoot incidents and spring shoot lengths of red bayberry were increased with increasing PB concentrations, but the optimum fruit yield and quality were obtained from foliar-applied PB at 100–200 mg L^?1 at full bloom. Foliar application of PB increased the contents of N and K in the leaves with increases of PB concentrations up to 300–600 mg L^?1. Fruit quality of red bayberry trees treated with PB or and boron fertilizer (BF) was improved at full bloom. Foliar application of PB reduced the percentage of fruit set by 62.1% in the year after treatment with PB but increased the yield by 49.0% the following year. Foliar application of PB at 100–300 mg L^?1 gave the most significant improvement in fruit quality: increase in fruit weight, soluble solid content, and the ratio of soluble solids (SS)?/?total acidity (TA) and decrease in total acidity. Foliar application of BF slightly reduced the fruit yields in the current year but significantly increased those the following year. Combined application of BF and PB or application of PB alone markedly reduced the fruit yields in 2006 by 40.5% and 43.8%, respectively, but markedly increased those by 44.6% and 17.8% in 2007, respectively. The effects of alleviating alternate bearing of red bayberry for different treatments followed the order of combined application of FB + PB > PB > BF > control. It is suggested that PB and BF can be used to alleviate alternate bearing.     

杨梅果的机械损伤试验和生物力学特性

为探讨在机械采摘条件下杨梅果的损伤机理与规律,该文依据机械手采摘果实的压缩、夹持、坠落等机械损伤形式,设计了杨梅果的力学特性试验方案,分析了杨梅果实的表型和成熟度等生物特性,应用圆球与平面接触的弹性力学模型理论以及试验数据,推导杨梅果的生物力学参数。分析得出了杨梅果的压缩弹性系数C、最大接触应力q和几种机械损伤杨梅果的力学特性方程和关系曲线。研究结果可为杨梅采摘机械手末端执行器的设计与采摘控制提供参考。     

氮钾配施对芋头产量和品质的影响

采用二次饱和D-最优设计,研究了氮钾肥配施对芋头产量和品质的影响,并建立了以氮、钾肥施用量为变量因子,芋头产量和品质为目标函数的二元二次数学模型。模型解析表明,氮、钾肥对芋头产量和品质均有显著影响,且钾肥的影响大于氮肥;氮、钾肥之间存在显著的交互效应。在氮(N)、钾(K2O)施用量分别为261.75kg/hm2、757.50kg/hm2以内,产量随施肥量的增加逐渐提高,超过此施用量,则产量下降。在本试验条件下,施肥量为N34.5～531.0kg/hm2,K2O.526.8～1057.2kg/hm2,芋头产量可达30000kg/hm2以上。     

施钾时期对甘薯产量及钾肥利用率的影响

为了明确不同时期施用钾肥对甘薯块根产量及钾肥利用率的影响,以济徐23为材料,进行大田试验。研究钾肥施用时期对甘薯块根干物质积累特性、干物质分配、钾肥利用率的影响。结果表明,不同时期施用钾肥均可提高块根产量,基施增产幅度最大,为26.09%,封垄期追施次之,高峰期追施最小。与对照处理相比,施用钾肥提高了块根膨大速率,基施和封垄期追施处理块根膨大前期增幅较大,而高峰期追施钾肥块根膨大后期增幅略高;基施处理显著降低全时期甘薯茎叶鲜重与块根鲜重的比值(T/R值),而封垄期追施处理显著降低生长中后期T/R值;施肥处理均可提高收获期块根干物质分配率,基施钾肥处理达到显著水平。基施钾肥处理钾肥产块根效率、钾肥收获指数、钾肥农学利用率和钾肥偏生产力显著高于其他施钾处理。基施钾肥通过提高钾肥农学利用率、偏生产力和钾肥收获指数,降低T/R值,促进块根膨大,最终获得高产。     

施钾对高油玉米和普通玉米吸钾特性及子粒产量和品质的影响

采用田间试验研究钾肥用量对高油玉米和普通玉米吸钾特性及子粒品质和产量的影响。结果表明,两品种钾素吸收最大速率随施钾量的增加呈增加趋势,在施K2O.90150.kg/hm2范围内,通油1号的钾素吸收最大速率大于四密25。成熟期通油1号的吸钾总量明显高于四密25,但其子粒产量却低于四密25。玉米子粒的钾素绝大部分来源于开花后根系的吸收。通油1号开花后根系钾素吸收量和成熟期子粒钾素吸收总量明显高于四密25。高油玉米通油1号含有较高的脂肪酸和蛋白质含量,但淀粉含量较低。施钾在提高产量的同时,增加了子粒中脂肪和蛋白质及其组分含量,但减少了淀粉总量和支链淀粉含量。表明子粒中淀粉、蛋白质、脂肪和产量之间存在内在联系。     

包膜氯化钾一次基施对棉花生长周期钾素供应、 产量及品质的影响

【目的】钾是影响棉花生长发育和纤维品质的重要因素,本文旨在探究一次基施控释钾肥对棉花产量、 品质和钾肥利用率的影响,为棉花合理施用钾肥提供理论依据。【方法】以国欣棉3号为试验材料,在氮磷肥相同的条件下,连续2年盆栽试验。设6个处理: 1)不施钾肥(CK); 2)一次基施普通氯化钾(KCl); 3)40%基施+60%初花期追施氯化钾(KClD); 4)一次基施硫酸钾(KS); 5)40%基施+60%初花期追施硫酸钾(KSD); 6)一次基施控释氯化钾(CRK),每个处理重复四次。测定了苗期、 蕾期、 初花期、 盛花期、 始絮期和收获成熟期土壤速效钾含量和棉花株高、 茎粗,调查了籽棉产量,分析了品质指标和钾素吸收量。【结果】控释钾肥一次性基施(CRK)较普通钾肥显著提高了初花期、 盛花期、 始絮期及收获期的土壤速效钾含量。CRK较KCl处理增产23.6%,比KS处理增产15.6%,比KClD处理增产16.0%,与KSD处理差异不显著。CRK较KCl处理显著提高了衣分值,其余处理间单铃重及衣分差异不显著。CRK显著提高纤维长度、 伸长率和断裂比强度,但马克隆值和整齐度与其他处理差异不显著。速效钾肥追施较一次基施处理显著增加了生物量和吸钾量,但均低于控释钾肥处理。CRK处理的钾素利用率较KCl处理显著提高41.9%~50.9%,较KS处理提高27.3%~29.9%,较KClD处理提高21.1%~25.2%。【结论】本试验采用的控释钾肥钾素释放高峰期(80~110天)与棉花养分吸收高峰基本吻合,在棉花上一次基施对不同生育期的钾素供应优于普通钾肥一次性基施,也好于普通钾肥基施加追施,较速效钾肥显著提高了棉花的产量、 品质和钾肥利用率。     

连续施用硫酸钾镁肥对柑橘的效应

以柑为试验材料,采用短期定位试验,研究了施用硫酸钾镁肥料对柑效应的影响。结果表明,施用各种钾肥对柑鲜果产量有极显著增产效果,且能提高叶片中钾素含量。在施用氮磷肥基础上,施用硫酸钾镁肥的增产效应明显,经济效益最佳。在本试验中,与施硫酸钾相比较,施用氯化钾的果实Vc含量略有下降,可滴定酸含量略有提高。