Potential of Biosolids from Shrimp Aquaculture as a Fertilizer for Broccoli Production

Shrimp biosolids (SB) are composed of shrimp fecal matter and decomposed shrimp feed and remain as debris in the bottoms of drained ponds used to culture shrimp. These biosolids are considered waste and usually disposed of in landfills. SB is a valuable source of N, P, K and a variety of other useful plants nutrients; however, SB contains high levels of Na. Field research was conducted to evaluate the potential of SB as a fertilizer source used with and without an inorganic fertilizer source (Osmocote 14N - 6P - 12K) to grow broccoli (Brassica oleracea italica). Yield of marketable heads/ha varied with SB/Osmocote (OSM) ratios. OSM at 75 kg/ha in combination with 9.0 MT SB/ha increased heads/ha significantly compared to lesser rates of each fertilizer source. This SB/OSM fertilizer regime contained a total of 263N - 116P - 99K - 99Na/ha. The biological yield increased 13% with OSM at 150 kg/ha and SB at 9.0 MT/ha, but if OSM was increased to 300 kg/ha, yield decreased significantly by 21% probably due to excessive fertilizer salts from both sources restricting plant growth. Lettuce field bioassays after broccoli production did not indicate that either fertilizer source persisted in the soil. The sodium in SB needs to be considered carefully whenever this material is used and SB should be evaluated in experimental trials before commercial use on other crops.     

Salinity and drought affect yield response of bell pepper similarly

Abstract

There is a growing realization that an increasing number of countries are approaching full utilization of their conventional water resources and that the quantity of good-quality water supplies available to agriculture is diminishing. Effects of irrigation regime and irrigation water salinity on bell pepper including yield, fruit number and quality, vegetative and root growth, evapotranspiration and water use efficiency were investigated in this study by conducting two different experiments. Six different salinity levels of irrigation water and four different irrigation regimes were used as treatments. Considering the results from irrigation water salinity experiment, it can be concluded that as soil salinity increases, water consumption, water use efficiency, yield and other vegetative growth parameters of bell pepper were decreased. A polynomial relationship between soil salinity and water consumption was observed. It was found that bell pepper is moderately sensitive to salinity with a 1.2 dS m^?1 threshold and a 10.9% slope value. In the irrigation regime experiment, limited irrigation caused decreases in water consumption, yield and vegetative growth of bell pepper. Yield response factors were close in the cases of irrigation regime (1.50) and irrigation water salinity (1.40). Total soluble solids of bell pepper were increased due to both irrigation water salinity and water application rate but not dry matter ratio. Considerable water consumption decreases because of salinity were determined. Therefore, the effect of irrigation water salinity should be considered in irrigation management to prevent excess saline water application and to protect the environment.     

基于临界氮浓度模型的日光温室甜椒氮营养诊断

临界氮浓度稀释曲线是诊断作物氮营养状况的有效手段。该研究基于2 a温室小区试验,以参考作物蒸发蒸腾量（reference crop evapotranspiration,ET0）为基准,设置4个灌溉水平（105%ET0、90%ET0、75%ET0、60%ET0）和4个氮素水平（300、225、150、75 kg/hm2）,构建和验证基于地上部生物量的甜椒在不同水分条件下的临界氮浓度稀释曲线经验模型。结果表明,植株氮素吸收量、地上部生物量、经济产量和水分利用效率（water use efficiency,WUE）随灌水量增加呈先增加后减小的趋势;灌溉水平75%ET0和90%ET0下,最优施氮量差异较小,且可获得较高经济产量和WUE,但经济产量和WUE不能同时达到最佳。75%ET0灌溉水平可获得高于90%ET0灌溉水平约11%的水分利用效率,且经济产量仅降低约3%,鉴于研究区水资源较短缺,灌水量75%ET0施氮量190 kg/hm2左右为最佳策略。该研究可为西北地区温室甜椒实时精准灌水施氮提供理论依据和技术支持。研究可为西北地区温室甜椒实时精准灌水施氮提供理论依据和技术支持。     

控释氮肥对辣椒的生理效应及利用率研究

利用盆栽试验和田间生物试验,研究了控释N肥脲醛类肥料品种脲甲醛(UF)与速效N肥不同品种对辣椒生长、形态指标、产量及利用率的影响;并采用覆膜和露地2种大田栽培法探讨了不同控释肥用量对辣椒产量和品质的肥料效应。结果表明,辣椒对控释N肥中N的吸收利用率最高,达44.4%,较其它N肥品种提高17.46%～46.05%,其产量为CK的1.88倍。N肥品种的增产效应顺序为UFCO(NH2)2NH4NO3NH4HCO3;UF处理,辣椒的果长、果宽、单果重及座果率等指标明显高于其它速效N肥品种。控释N肥用量试验表明,产量与用量密切相关,以600kg/hm2投入可取得较高的产量和经济效益,过量施用,效益显著下降。控释肥相同用量,覆膜栽培较露地栽培增产15.16%～16.45%;辣椒总糖、维生素C含量有随施用量增加而增加的趋势,但对干物质量及总酸度的影响较小。     

Effects of irrigation and nitrogen rates on foliar mineral composition of bell pepper

Irrigation and nitrogen fertilization are two important aspects of bell pepper production. Yet, limited information is available on the effect of irrigation on foliar nutrient content. Bell pepper were grown on bare ground under two nitrogen fertilization rates (11 and 19 kg N week^‐1) and irrigated according to an irrigation scheduling model based on weather data and crop age. Eight irrigation rates ranged between 36 and 148% of the model rate. Leaf samples were taken at first bloom (62 days after transplanting, DAT) and after final harvest (84 DAT). Yield response and the foliar content of all essential elements determined [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), boron (B), copper (Cu), iron (Fe), molybdenum (Mo), manganese (Mn), zinc (Zn)] responded linearly or quadratically to irrigation rates and most foliar nutrient contents remained within or above the sufficiency range. Foliar mineral content tended to be lower at 84 DAT as compared to 62 DAT. Only Ca became deficient under high irrigation rates on 84 DAT. Current fertilization recommendations for bell pepper and 100% of the model irrigation rate resulted in highest yield. These results suggest that the high N rate supplied as calcium nitrate should be used when multiple bell pepper harvests are expected.     

不同用量专用生物炭基肥对贵州朝天椒提质增效的影响

为探究生物炭基肥对贵州黄壤朝天椒的施用效果,采用大田试验,以自制生物炭基肥为供试材料,研究不同生物炭基肥施用量[1 758(BCF1)、2 167.5(BCF2)、2 550(BCF3)、2 932.5(BCF4)和3 315 kg·hm^-2(BCF5)]对贵州朝天椒产量、品质、养分积累、肥料利用率和经济效益的影响。结果表明,与习惯施肥(FP)处理相比,施用生物炭基肥可以显著提高朝天椒产量,其中鲜椒增产12.0%~32.8%、干椒增产12.6%~31.6%,且以BCF2处理效果最佳;施用生物炭基肥对朝天椒的硝酸盐和Vc含量影响显著,其中硝酸盐含量降低了3.9%~14.4%、Vc含量提高了1.0%~19.3%,但对还原糖和游离氨基酸含量无影响;与FP处理相比,施用生物炭基肥使氮、磷、钾肥的农学效率分别提高了4.97~13.93、8.49~26.41 kg·kg^-1,BCF1、BCF2 和 BCF3 处理的钾肥农学效率提高了3.12~8.32 kg·kg^-1,以BCF1处理为最高,氮、磷、钾肥的表观利用率分别提高了24.11~43.90、2.63~7.76、7.50~44.60个百分点,其中BCF2处理的氮肥表观利用率和钾肥表观利用率最高,分别为55.0%和74.1%,BCF1和BCF2处理的磷肥表观利用率最高,均为10.3%;与FP处理相比,施用生物炭基肥后的朝天椒纯收入提高了19.4%~74.8%,以BCF2效果最佳。综上,本试验条件下生物炭基肥施用量为2 167.5 kg·hm^-2时朝天椒生物效应和经济效益最好,可作为贵州朝天椒种植的最佳施用量。本研究结果为生物炭基肥在贵州黄壤朝天椒高产栽培技术中的应用提供了理论依据。     

Influence of colored plastic mulch on soil temperature,growth, nutrimental status,and yield of bell pepper under shade house conditions

The aim of this study was to determine if plastic mulch films may have positive effects on bell pepper plants grown under shade house conditions. The experimental design was split-plot, where large plots contained four plastic mulch films (black, aluminum, silver, and white) compared to bare soil and small plots contained two bell pepper cultivars. Plant shoot dry weight was higher in plastic mulch treatments than in bare soil. The net photosynthesis rate in the cultivar SWG-46 exceeded in net photosynthesis with respect to the cultivar SWG-42 in one of three sampling dates. Nutrients in leaf showed a similar behavior in plastic mulch treatments than the control but the total content of nitrogen (N), potassium (K), and sulfur (S) was increased. The total yield was higher in black plastic mulch than in the other plastic mulch colors and lowest in the control.     

Scheduling Drip Irrigation for Bell Pepper Grown with Plasticulture

Producing economical yields of bell pepper (Capsicum annuum L.) while conserving water and nutrients requires an integrated approach to fertilization and irrigation. Detailed fertilization recommendations exist for bell peppers grown in Florida, but current irrigation recommendations are based on historical weather data and year-to-year adjustments. The objective of this study was to develop and test a crop factor (CF) for bell peppers grown with plasticulture and irrigated daily. Crop water use (ETc) was calculated daily by multiplying CF with Class A pan evaporation (Ep). Values for the proposed CF were 0.20, 0.40, 0.80, 1.00, and 0.80 for periods 1–2, 3–4, 5–11, 12, and 13 weeks after transplanting, respectively. Daily Ep values were converted, to irrigation volumes using 10 mm Ep = 835 L/100 m of bed length. ‘Brigadier’ bell peppers were established in a factorial combination of 75%, 100%, and 125% of the recommended 224 kg N/ha rate and 33%, 66%, 100%, and 133% of the reference irrigation rate (I3) based on the proposed CF. Soil water tension (SWT) was monitored twice weekly in all the plots receiving the 100% nitrogen (N) rate. The numbers of days SWT remained below the recommended 15 kPa increased quadratically in both years as irrigation rate increased. Only the 100% and 133% I3 irrigation rates maintained SWT within the 0 to 15 kPa range at 15 and 30 cm depths on most days in 2001 and 2002. In 2001, bell pepper yields tended to increase as N rate increased. For 125% N rate, total, marketable, and fancy bell pepper yields responded quadratically to irrigation rates. Highest yields occurred between 115% and 124% of I3. In 2002, bell pepper yield did not respond to irrigation rate, and responded quadratically and linearly for N rates of 75%, 100%, and 125%, respectively. Highest bell pepper yields occurred with 125% N rate and 133% I3 irrigation rate. These results suggest that highest yields of bell pepper grown in the spring with plasticulture may be achieved with a combination of 125% of the University of Florida recommended N rate and irrigation scheduled in real time using 1.25 × CF test values of 0.25, 0.50, 1.25, 1.00, and 1.00 for the periods 1–2, 3–4, 5–11, 12, and 13 weeks after transplanting, respectively, with 10 mm Ep = 835 L/100 m of bed length.     

Drip fertigation with nitrogen and potassium and postharvest susceptibility to bacterial soft rot of bell peppers

In 1991 and 1992, drip irrigation was used to apply various rates and timings of nitrogen (N) and potassium (K) to black polyethylene plastic‐mulched bell pepper (Capsicum annuum L.) to determine the effect on fruit quality and susceptibility to postharvest bacterial soft rot (Ervinia carotovora subsp. carotovora). Neither rate nor application timing affected total yield in either year. In 1991, the high fertilizer rate (266–309 kg/ha of N and K, respectively) increased class 1 yield in the first harvest and reduced total discards. In 1992, a year with a colder than average spring, the low fertilizer rate (70–81 kg/ha of NK) increased class 1 yield in the first harvest. Mid‐ or late‐season fertigation produced more second harvest yield and less discards than the first harvest in 1991, but not in 1992. Fruits of plants fertilized with high N and K rates had greater N and dry matter concentration. No differences in color or wall thickness at harvest were detected among treatments. Stored fruits turned red slower with the late season low fertilizer rate. There were no differences in rate of weight loss during storage at 10°C. No differences in progression of bacterial soft rot were detected among treatments in 1991, but the higher fertigation rates or late timing application increased resistance in 1992.     

铜基营养叶面肥对辣椒光合特性、产量、品质及防病效果的影响

通过连续2年的田间试验,采用随机区组设计,设置6个处理,以喷清水为对照,研究了3种铜基营养叶面肥及传统波尔多液和美国商品铜制剂Kocide 2000对辣椒产量、品质、叶片叶绿素含量及光合特性、微量元素的含量及积累量、防病效果以及对土壤酶活性的影响。结果表明,喷施CFFe、CFZnB、CF、KCD可以显著增加辣椒叶片叶绿素含量,以CFFe处理增加最多,最高增幅为20.13%,其次为CFZnB处理,增幅为16.19%～18.13%;还可显著增加辣椒叶片的光合速率、气孔导度和蒸腾速率,显著降低胞间CO2浓度。喷施BDM、KCD、CF、CFFe、CFZnB可以显著增加辣椒各器官全铜含量及积累量;喷施CFZnB、CFFe、CF、KCD可以显著增加辣椒各器官全锌含量及积累量;喷施CFFe、CFZnB、CF、KCD可以显著增加辣椒各器官全铁含量及积累量。喷施CFFe、CFZnB、CF、KCD及BDM能显著降低辣椒初果期和盛果期的病情指数。CFFe、CFZnB处理土壤脲酶活性最高;各处理及CK土壤过氧化氢酶活性均比BDM处理增加显著;CFFe、CFZnB、CF、KCD处理土壤蔗糖酶活性均比CK增加显著。CFFe处理辣椒营养品质最好,其次为CFZnB处理。喷施CFFe、CFZnB、CF、KCD可以显著增加辣椒产量,以CFFe处理增产最多,最大增幅为13.22%;其次为CFZnB处理,增幅为11.93%～12.52%。喷施CFFe、CFZnB、CF可以显著增加辣椒产量,以CFFe处理增产最多,其次为CFZnB处理;喷施CFFe、CFZnB、CF可以显著改善辣椒的品质,CFFe处理的辣椒营养品质最好;其次为CFZnB处理;山东农业大学研制的铜基营养叶面肥作为一种杀菌防病和植物营养保健双重功能的叶面肥,既能显著增加辣椒产量、改善辣椒品质,又具有一定的杀菌防病效果,推荐使用加铁铜基营养叶面肥和加锌硼铜基营养叶面肥。     

生物炭与脲酶抑制剂及保水剂配施对贵州辣椒的影响

为探究生物炭与不同土壤添加剂配施在贵州黄壤辣椒上的施用效果,采用大田试验,选用酒糟生物炭、脲酶抑制剂和保水剂作为供试材料,研究增施生物炭(FB)、生物炭与脲酶抑制剂(FBU)或保水剂(FBW)两两配施、生物炭与脲酶抑制剂和保水剂(FBUW)三者同时施用对辣椒产量、品质、养分吸收累积、肥料利用率和经济效益的影响。结果表明,与常规施肥(F)相比,增施土壤添加剂可显著增加辣椒鲜产,增加幅度17.91%~28.74%,产值增加20 351~29 700元·hm^-2,增幅为167.14%~243.93%,其中以三者同时施用(FBUW)效果最佳,达到20 938 kg·hm^-2;生物炭与脲酶抑制剂或(和)保水剂配施可降低辣椒果实中硝酸盐含量6.32%~34.00%,以FBUW降幅最大,且三者同时施用还可显著提高果实中的游离氨基酸含量;与F相比,增施土壤添加剂使氮、磷、钾肥的表观利用率分别提高了4.13~10.80个百分点、-0.98~8.72个百分点和6.36~27.56个百分点,而氮、磷、钾肥的农学效率则分别提高了8.09~12.98、16.18~25.97和8.99~14.42 kg·kg^-1,均以FBUW最佳;与F相比,增施土壤添加剂后的辣椒纯收入提高了0.83%~23.21%,以FBUW效果最佳。综上,在常规施肥基础上,生物炭、脲酶抑制剂和保水剂三者同时配施产生的协同效应优于单独施用或两两配施。本研究结果为土壤添加剂在贵州黄壤辣椒高产栽培技术中的应用提供了理论依据。     

甜椒对不同形态氮素的吸收和分配

甜椒对不同形态氮素的吸收利用有显著差异。幼苗期及发棵期ＮＨ ＋４ Ｎ 对生长有利,而盛果期则以ＮＯ－３ Ｎ 有利。同种形态氮素因施用时期不同而氮素利用率差异很大,以盛果期追肥利用率最高,为４１８ ％ ～４５８ ％ ; 基肥利用率为３３６ ％ ～３６７ ％ 。不同时期施肥的肥料氮在各器官的分配不同,基肥及初花期施肥氮素主要流向茎叶,占总吸收量的７５ ％ 左右;盛果期追肥以果实分配较多,占总吸收量的６０ ％以上。对植株氮素来源的分析表明,仅４００ ％ ～４１５ ％ 的氮素来自于肥料,而近６０ ％ 的氮素来自于土壤。     

Plant growth and fruit quality of two pepper cultivars under different potassium levels of nutrient solutions

Potassium (K) is a major nutrient element that has effects on growth, yield, and quality production of agricultural crops. In the present study, the effects of various K concentrations in a nutrient solution including 150, 235, 300, 400, or 500 mg K L^?1 were evaluated on two pepper cultivars; chili pepper (Capsicum annuum Avicolare) and bell pepper (California Wonder) under greenhouse conditions. Hoagland's formula was used for preparation of nutrient solutions. The vegetative growth parameters including plant height, leaf area, SPAD value, and shoot fresh weight were significantly increased by 300 mg L^?1 K in both cultivars. The highest yield and fruit quality parameters including fruit length/diameter ratio, fruit dry matter percentage, fruit vitamin C, total soluble solids, and titratable acidity in chili pepper and bell pepper were obtained under application of 300 and 400 mg K L^?1 in nutrient solution, respectively. In either cultivar there was increase in leaf K, nitrogen, and zinc concentrations, while in bell pepper calcium was reduced by higher K levels in the nutrient solution. The results indicate that for better growth and quality production of pepper, higher levels of K in nutrient solutions can be beneficial.     

Effects of biochar and fertilizer sources on nitrogen uptake by chilli pepper plants under Mediterranean climate

This study determined N uptake by serrano chilli pepper for two years and evaluated the effects of biochar amendment or organic N (org-N) fertilizer on N use under a Mediterranean climate. A field experiment was conducted using microplots from 2016 to 2017 in California, USA. Treatments included biochar amendment rates [0 (control), 10, 30 and 50 tons (t) ha⁻¹] biochar, all with 100% inorganic N fertilizer (165 kg N ha⁻¹), and org-N fertilizer applications at 50%, 75% and 100% of the total available N supply. Pepper yield, vegetative biomass, N uptake, ammonia (NH₃) volatilization and changes in soil organic carbon (SOC), and nitrate were determined. Pepper yield was highest in the 50% org-N and lowest in the 50 t ha⁻¹ biochar treatment during the first year. There were no differences in fruit yield among the organic treatments during the second year, and all were higher than that from the control. The 100% org-N treatment had less NH₃ volatilization than all other treatments during the first year. The two-year results showed that chilli pepper plants sequestered 4.6‒6.1 kg N to produce one ton fresh pepper fruits. During the first year, the 50% org-N treatment resulted in the highest N productivity or yield with lowest projected N fertilizer application requirements as compared to other treatments although there were no differences among all treatments in the second year. Thus, a combination of inorganic and org-N fertilizers can be an effective strategy to improve soil N productivity in long-term management.     

海南有机肥替代氮肥对辣椒生长和品质的影响

过量施用氮肥会提高蔬菜中硝酸盐和亚硝酸盐含量,且易造成环境污染。以优化施肥配方为基础,设置对照(100%化肥),另外3个处理分别为20%、40%、60%有机肥替代化肥,4个处理的氮肥用量相同,研究有机肥部分替代氮肥对辣椒生长、品质和土壤性状影响。结果表明,不同处理的辣椒产量无显著差异。有机肥替代氮肥可显著提高辣椒果实中Vc含量,降低亚硝酸盐含量。40%和60%处理有机肥叶片、茎秆生物量以及株高、冠幅等指标在后期显著低于化肥和20%替代处理。有机肥替代氮肥显著提升了土壤pH值和有机质含量。可见,有机肥替代氮肥不会造成海南辣椒前期生长、产量、外观品质下降,且有助于酸性土壤改良,其合理的替代比例是20%。     

滴灌水肥管理对温室冬春茬辣椒产量与风味的影响

【目的】探究滴灌水肥管理措施对温室辣椒产量与风味品质的影响,明确不同生育阶段适宜土壤含水量控制值,提出高产与增香提味的滴灌水肥管理方案。【方法】采用研发的全水溶滴灌专用肥,2019和2020年开展了温室冬春茬羊角型辣椒滴灌水肥协同试验。滴灌水量(W)和专用肥量(F)分别设计3个水平,共9个水肥组合处理。2019年总灌水量分别为1703.3 m³/hm² (W1)、2423.3 m³/hm² (W2)、3143.3 m³/hm² (W3),总专用肥量分别为712.5 kg/hm² (F1)、1087.5 kg/hm² (F2)、1462.5 kg/hm² (F3);2020年总灌水量分别为1913.3 m³/hm²(W1)、2753.3 m³/hm² (W2)、3593.3 m³/hm...     

Concomitant biocontrol of pepper Phytophthora blight by soil indigenous arbuscular mycorrhizal fungi via upfront film-mulching with reductive fertilizer and tobacco waste

Purpose

Both reductive disinfestation and germicide can suppress Phytophthora blight, while soil arbuscular mycorrhizal (AM) fungi also have biocontrol effects on soilborne diseases. However, the combined effects of reductive disinfestation and botanical germicide [e.g., tobacco (Nicotiana tabacum L.) waste] on pepper (Capsicum annuum L.) Phytophthora blight and soil AM fungi are at present unclear. The purposes of this work were to develop application strategy for dealing with pepper Phytophthora blight, and to explore the concomitant contribution from soil indigenous AM fungi.

Materials and methods

A field experiment with four treatments was carried out in a pepper continuous planting field, including normal film-mulching with common fertilizer (control), normal film-mulching with reductive fertilizer (RF), upfront film-mulching with reductive fertilizer (UM+RF), and upfront film-mulching with reductive fertilizer and tobacco waste (UM+RF+TW). Phytophthora blight severity index, root mycorrhizal colonization rate, and the biomass and nutrient (N, P, and K) concentrations of shoots, roots, and fruits of pepper were measured. Soil pH, organic C, mineral N, available P, available K, acid phosphatase activity, and AM fungal abundance were also tested. The Pearson correlation analysis was carried out among plant and soil parameters.

Results and discussion

RF tended to increase pepper fruit yield compared with control, and UM+RF tended to decrease Phytophthora blight severity in relative to RF, while UM+RF+TW tended to decrease blight severity and increase fruit yield compared with UM+RF, and had a significantly (P?<?0.05) lower blight severity and a significantly higher fruit yield in comparison with control. UM+RF+TW also significantly decreased soil pH, and significantly increased AM fungal population and colonization, as well as soil acid phosphatase activity and available P concentration. In addition, UM+RF+TW had a significantly higher fruit K accumulation ratio, which negatively correlated with blight severity and positively correlated with fruit yield. However, fruit K accumulation ratio positively correlated with fruit P accumulation ratio, which was greatly elevated by the enhanced mycorrhizal colonization.

Conclusions

The coalition of reductive disinfestation (upfront film-mulching with reductive fertilizer) and tobacco waste had the greatest suppression of pepper Phytophthora blight, and the highest fruit yield and AM fungal population. It suggests that combined application of reductive disinfestation and botanical germicide has superposition in inhibiting Phytophthora blight and increasing fruit yield, and there seems to be a concomitant biocontrol by soil indigenous AM fungi which could enhance P and K transfer from plant to fruit.

     

Under filed conditions,mycorrhizal inoculum effectiveness depends on plant species and phosphorus nutrition

Abstract

The cultivation of horticultural crops, such as green peppers, tomatoes, eggplants and bell peppers is very common in semi-arid Mediterranean climate conditions. Two field experiments were performed to determine the effect of mycorrhizal species, plant species and phosphorus levels on mycorrhizal effectiveness and phosphorus (P) and zinc (Zn) nutrient uptake. In the first experiment, under field conditions, four plants species were inoculated with five arbuscular mycorrhizae (AM) species. In the second field experiment, under the same soil conditions, the same plant species were treated with three levels of phosphorus (P), i.e., control; 50?kg and 100?kg P₂O₅ ha^?1. The most effective mycorrhiza species Claroideoglomus etunicatum selected in the first experiment was used in the second field first experiment. In the first experiment, fruit yield enhancement, yield increase, inoculation effectiveness and nutrient concentration in the plant leaves were analyzed. Under field conditions, plant species growth is strongly dependent on the species of AM fungi. Tomato and green pepper plants were inoculated with Cl. etunicatum, eggplants were inoculated with Funneliformis mosseae and bell peppers were inoculated with Rhizophagus clarus, which are high fruit-yielding plant species. In general, Fu. mosseae and Cl. etunicatum increased the yield of the tomatoes, green peppers and eggplants. It seems mycorrhiza species specific to plant species. In the second experiment, mycorrhizal inoculation with P fertilizer application, in particular a moderate amount of P (50?kg ha^?1 P₂O₅) fertilizer increased the green pepper, bell pepper and tomato fruit yield compared with non-inoculated plants and non-P fertilizer application treatments. Increasing the application of P level reduced the mycorrhizal inoculation effectiveness (MIE). The results indicate that for all four solanaceae family plants 50?kg ha^?1 P₂O₅ is a P level threshold for mycorrhizal development, which enhanced plant growth and addition of fertilizer over 50?kg ha^?1 P₂O₅ reduced MIE. P and Zn uptake were significantly increased with mycorrhizal inoculation. These findings are supported by our hypothesis that mycorrhiza inoculation can reduce mycorrhizal dependent horticultural plants P fertilizer requirement.     

不同腐殖酸复合肥施用量对辣椒产量及其养分利用率的影响

试验研究不同腐殖酸复合肥施用量对辣椒产量及其养分利用率的影响结果表明 ,随施肥量的增加而辣椒叶片N、P、K累积量逐渐增大 ,果实N、P、K累积量呈二次抛物线趋势变化 ,且施肥量过大时不利于营养元素向果实中的转移。肥料生产效率及N、P、K养分利用率均随施肥量的增大而降低 ,肥料对辣椒产量的贡献率以及辣椒产量随施肥量的变化与辣椒果实营养元素累积量变化趋势相一致     

保山市冬早大棚辣椒氮磷钾肥料优化施用

针对保山区域冬早大棚辣椒氮磷钾肥料效应缺乏系统研究,存在偏施氮肥、盲目施肥和过量施肥的现象,采用三因素五水平二次正交旋转组合设计,通过田间小区试验,研究氮磷钾肥料效应模型,通过频率分析研究高产优化施肥组合方案。保山大棚辣椒氮磷钾肥料效应回归模型Y=38 180.4+19.865 7N+16.102 7P+16.150 1K+0.026 6NP+0.012 4NK-0.006 8PK-0.025 8N~2-0.038 5P~2-0.014 1K~2,目标产量大于53 000kg/hm~2的优化施肥组合方案为N 568.9~631.9 kg/hm~2,P_2O_5 242.7~321.3 kg/hm~2,K_2O 684.6~794.8 kg/hm~2,氮磷钾比例为1∶0.47∶1.23,与当地施肥量水平相比,温暖区氮肥用量平均降低36.3%,温热区氮肥用量平均降低23.1%。氮磷钾肥配合施用能显著提高大棚辣椒产量,氮肥效应达极显著水平,磷肥和钾肥效应达显著水平,效应排序为氮肥钾肥磷肥;氮磷和氮钾的交互效应为显著正效应,N用量在175~425 kg/hm~2时,辣椒产量随着P_2O_5用量的增加呈先增后降趋势,增幅随着磷肥用量的增加而减小,N用量在175~573.7 kg/hm~2时,钾肥效应趋势与磷肥一致,在高氮情况下,辣椒产量随着磷肥(或钾肥)用量的增加而增加。