Application of QUEFTS Model for Site-Specific Nutrient Management of NPK in Sweet Potato (Ipomoea batatas L. Lam)

Sweet potato productivity in India is either stagnated or lowering down over the past many years. The main reasons for low yield are conventional blanket recommendation of fertilizers, lower nutrient-use efficiency and imbalance in the use of fertilizers. Recommendation of major nutrients, nitrogen, phosphorus, and potassium (NPK), based on quantitative approaches will augment sweet potato production per unit area by increasing the nutrient-use efficiency. The present study calibrated the Quantitative Evaluation of Fertility of Tropical Soils (QUEFTS) model for the estimation of NPK requirements and fertilizers recommendations for different target yields of sweet potato. The QUEFTS basically works on the principle of NPK nutrient interactions and climate-adjusted yield potential of a region. Published data sets from several field experiments related to NPK carried out till date were collected to reflect the environment variability. The results of the present study showed that to produce one ton tuber, 16:6:18 kg N, P, and K, respectively, would be needed with the internal efficiencies of 61:167:57 kg tubers kg^?1 NPK removed. The maximum accumulation and dilution (kg tuber kg^?1 nutrient removed) of N (40, 80), P (96, 272), and K (30, 85) were also derived as standard parameters in QUEFTS for optimum fertilizer recommendation in tropical and subtropical regions of India. The observed yields of sweet potato with different amounts of nutrients were in agreement with the values predicted by the model. Therefore, it is utmost important to have the results of the study validated in major growing environments of India for fertilizer recommendation in sweet potato.     

Quantitative determination of NPK uptake requirements of taro (Colocasia esculenta (L.) Schott)

Taro yield in many parts of the world is stagnant mainly due to conventional blanket recommendation of fertilizers, lower nutrient use efficiency and imbalance in the use of nutrients. The Quantitative Evaluation of Fertility of Tropical Soils (QUEFTS) model was used for determining the region specific balanced NPK uptake requirements and recommendations for a target yield of taro. The constants for minimum and maximum accumulation (kg cormel kg^?1 nutrient) of N (33 and 177), P (212 and 606) and K (25 and 127) were derived as standard model parameters. The results showed that taro requires N, P and K accumulation of 12.97, 2.75 and 17.47?kg t^?1 of cormel yield, suggesting an average NPK ratio in the plant dry matter of about 4.7:1:6.4. The NPK fertilizer requirements for different potential yield situations were also calculated. The results need to be validated in major taro growing regions.     

马铃薯田线虫病害发生及防治

近些年马铃薯土传病害发生严重,除了真菌、细菌等病原物引起的病害外,线虫病成为威胁马铃薯生产的又一大病害.危害马铃薯的植物寄生线虫主要有马铃薯腐烂茎线虫(Ditylenchus destructor)、鳞球茎线虫(Ditylenchus dipsaci)、马铃薯孢囊线虫(马铃薯白线虫(Globodera rostochi...     

Soil and tuber calcium affecting tuber quality of processing potato (Solanum tuberosum L.) cultivars grown in Hokkaido,Japan

Calcium (Ca) nutrition for potato (Solanum tuberosum L.) is important to increase tuber Ca concentration and improve potato tuber yield and quality. High tuber Ca content among other benefits mitigates incidence of blackspot bruise through maintenance of membrane health and regulation of biochemical reactions that leads to potato tuber discoloration. However, growers avoid application of Ca fertilizer in potato production in the belief that it causes potato common scab in Hokkaido, Japan. This study was conducted in Hokkaido to determine the current status of soil Ca and tuber Ca content levels, and its effect in mitigating incidence of potato bruise. Soil and tuber samples were collected from 90 and 80 fields in Tokachi and Kamikawa districts, respectively, in 2013 and 2014. Soil samples were analyzed for base saturation, Ca saturation, and exchangeable Al. Tuber Ca content and susceptibility of tubers to bruising were also evaluated. This study found that (1) 81% and 76% of soils collected from Tokachi and Kamikawa district, respectively, were deficient in Ca level, (2) tuber Ca content was lower than the reported value (250 mg kg^?1) considered to mitigate incidence of bruise, and (3) incidence of bruise were influenced by both tuber specific gravity and Ca content. There is urgent need to apply Ca fertilizer to attain increased soil Ca levels and improve quality of tubers.     

Simulation of fertilizer requirement for irrigated wheat in eastern India using the QUEFTS model

Abstract

Crop modelling can provide us with a vast amount of real-time information about fertilizer dose to achieve the target yield, crop conditions, etc. Nutrient-use efficiency in wheat is low because of conventional blanket and imbalanced fertilizer use. Estimation of fertilizer requirements based on quantitative approaches can assist in improving yields and nutrient-use efficiency. Field experiments were conducted in 20 sites in eastern India to assess the soil supply, requirement and internal efficiency of nitrogen (N), phosphorous (P), potassium (K) and zinc (Zn) in wheat. The data were used to calibrate the QUEFTS (QUantitative Evaluation of the Fertility of Tropical Soils) model for site-specific, balanced fertilizer recommendations. The parameters of maximum accumulation (a) and maximum dilution (d) in wheat were calculated for N (35 and 100 kg), P (129 and 738 kg), K (17 and 56 kg), and Zn (21502 and 140244 mg). Grain yield of wheat showed good correlation with N (R² = 0.937??), P (R² = 0.901??) and K uptake (R² = 0.801??). The NPK ratio to produce 1 ton grain yield of wheat was derived to be 4.9:1.0:8.9. The relationships between chemical properties and nutrient supplying capacity of soils were also established. The model was validated using the data of four other experiments. Observed yields with different amounts of N, P, K and Zn were in good agreement with the predicted values suggesting that the validated QUEFTS model can be used for site-specific nutrient management in wheat.     

Different pre-sprouting methods for early tuber harvest in potato (Solanum tuberosum L.)

Abstract

Earlier harvest of potatoes (Solanum tuberosum L.) can be achieved by different treatments of the seed tubers. This can be important, for example, in areas with a short growing season and in organic farming. In a pot experiment, different pre-sprouting methods were evaluated for four cultivars. The experiment consisted of (a) untreated seed tubers stored at 4 °C until planting, (b) traditional pre-sprouted tubers (P) and (c) pre-sprouted tubers with stimulation of adventitious root formation (PR). Pre-sprouted seed tubers have earlier and faster tuber formation, but often lower yield than non pre-sprouted tubers if there is no restriction of the growing season. The PR method developed here, where tubers were sprayed with water to stimulate adventitious root formation and give faster development and tuber initiation than conventional pre-sprouting, can be of value when the growing season is restricted or if early harvest is important. Initial emergence of the pre-sprouted potatoes was monitored in two pot experiments. Emergence was faster for the pre-sprouted treatments compared with the control, but there were no significant differences between the two pre-sprouting methods. At harvest, the pre-sprouted treatments gave higher yield than the control for all growing periods, methods and cultivars, although the differences were not significant for every combination. The cultivars Matilda, Cicero, Ovatio and Superb seemed to respond more positively in terms of yield to PR treatments than cv. Ditta. The new method for stimulating adventitious root formation developed here will substantially help growers to achieve earlier harvests.     

Effect of humic acid multinutrient fertilizers on yield and nutrient use efficiency of potato

A field experiment was conducted to study the effect of humic acid multinutrient fertilizers like Grow Flow 45H and HA-NPK complex on crop yield, nutrient content and uptake, and nutrient use efficiency of potato. Application of Grow Flow 45H (humic acid multinutrient liquid fertilizer) at recommended dose increased the tuber yield by 9.3% as compared to chemical fertilizer. Nitrogen (N), phosphorus (P) and potassium (K) content of the Grow Flow 45H treated plants were 2.89, 0.33 and 1.58% in shoots and 1.89, 0.21 and 1.03% in tubers, respectively which were significantly higher than the other treatments. Grow Flow 45H increased the N, P and K use efficiencies by 16.4%, 9.3% and 18.3% respectively over chemical fertilizer. Though HA-NPK complex fertilizer (developed in the laboratory) was not significantly different from chemical fertilizer in respect of yield, the contents and uptake, and use efficiencies of N, P and K; however the former was found better than the latter.     

立式深旋耕作对西北半干旱区马铃薯水肥利用和产量的影响

[目的]立式深旋耕作能提高土壤供水能力和促进作物根系发育,有利于作物对养分的吸收利用.[方法]在西北黄土高原半干旱区于2016-2018年布设马铃薯定位试验,设计立式深旋耕作40 cm(VRT)、深松40 cm(SS)和旋耕15 cm(TT)3个处理.在马铃薯播期、盛花期和收获期测定土壤含水量、碱解氮、有效磷、速效钾含...     

Mycorrhizal influence on storage metabolites and mineral nutrition in seed propagated potato (Solanum tuberosum L.) plant

Abstract

Potato (Solanum tuberosum) showed a well-established mutualistic association with arbuscular mycorrhizal fungi. In the present study, earthen pots containing autoclaved soil were taken in which surface sterilized potato seeds were sown. The seed sowed earthen pots were inoculated by sterilized spores of arbuscular mycorrhizal fungi along with sterilized inoculated maize-root fragments, while the rest half of the seed filled pots, without any inoculation depicting control but were provided with non-inoculated maize root fragments. The inoculation was performed twice; first inoculation was done 3 days prior to sowing of potato seeds and second at the time of seedling emergence. Sampling of the inoculated as well as of control plants was performed at 20-day intervals till 80?days after tuber initiation. An increment in the level of metabolites as well as mineral nutrient was found in mycorrhizal inoculated potato tubers in contrast to non-inoculated. Our work demonstrates that inoculation has a great potential in enriching storage metabolites and nutrients in potato plant in low yielding soils.     

Influence of arbuscular mycorrhizal fungi on storage metabolites,mineral nutrition,and nitrogen-assimilating enzymes in potato (Solanum tuberosum L.) plant

Mycorrhizae are fungal symbionts forming mutualistic relationship with plant roots. In this study, surface-sterilized potato tubers were sown in earthen pots filled with sterile soil. Half of the pots were inoculated with sterilized arbuscular mycorrhizal fungi (AMF) spores and sterilized inoculated maize root fragments, and another half without any AMF inoculation representing control. Inoculation was done twice 3 days before sowing the tubers and on the onset of seedling emergence. Plants, along with their controls, were sampled at 20-day intervals upto 80 days after tuber initiation. The tubers of potato are shown to present a higher level of metabolites and mineral nutrition in the mycorrhizal inoculated compared to the non-inoculated. The results showed that AMF has a potential in enhancing potato production by increasing the storage metabolites, mineral nutrition in tubers and nitrogen assimilating enzymes in plant.     

干旱地区覆盖方式对土壤养分及马铃薯产量的影响

大田条件下,为研究不同覆盖方式对旱作区马铃薯土壤有机质、养分及产量的影响,试验设置白色半膜垄作(BB)、白色全膜垄作(BQ)、白色半膜垄作+垄沟秸秆覆盖(BJ)、黑色半膜垄作(HB)、黑色全膜垄作(HQ)、黑色半膜垄作+垄沟秸秆覆盖(HJ)、秸秆覆盖垄作(JL)及裸地垄作种植(CK)8个处理.结果表明:不同覆盖方式均能...     

Long-Term Effect of Lime,Mycorrhiza, and Inorganic and Organic Sources on Soil Fertility,Yield, and Proximate Composition of Sweet Potato in Alfisols of Eastern India

A field experiment was conducted for five kharif seasons (2006–2011) in an Alfisol to study the effect of integrated use of lime, mycorrhiza, and inorganic and organics on soil fertility, yield, and proximate composition of sweet potato. Application of graded doses of nitrogen, phosphorus, and potassium (NPK) significantly increased the mean tuber yield of sweet potato by 44, 106, and 130 percent over control. Green manuring along with ½ NPK showed greater yield response over that of ½ NPK. The greatest mean tuber yield was recorded due to integrated application of lime, farmyard manure (FYM), NPK, and MgSO₄ (13.69 t ha^?1) over the other treatments. Inoculation of mycorrhiza combined with lime, FYM, and NPK showed a significant yield response of 10 percent over FYM + NPK. Conjunctive use of lime, inorganics, and organics not only produces sustainable crop yields but also improve soil fertility, nutrient-use efficiency, and apparent nutrient recovery in comparison to NPK and organic manures.     

Evaluation of White yam (Dioscorea rotundata) genotypes for arbuscular mycorrhizal colonization,leaf nutrient concentrations and tuber yield under NPK fertilizer application

Yield decline in yam may not only be due to soil nutrient depletion but also to the activity of soil microflora. Arbuscular mycorrhizal (AM) symbiosis helps in plant nutrition but may be affected by the application of fertilizer. The effects of nitrogen (N), phosphorus (P), and potassium (K) fertilizer rates on the AM colonization, leaf nutrient concentrations, and tuber yields of eleven genotypes of Dioscorea rotundata were investigated at Ibadan, Nigeria. The soil was ferric luvisol. Eleven genotypes were selected from the previously conducted screening of 75 genotypes of D. rotundata for fertilizer response. Four application rates: 0, 200, 400, and 600 kg ha^?1 of NPK 15-15-15 were applied in a split plot design with four replications. Fertilizer rate was the main plot and variety was the sub plot. Percentage AM colonization was significantly reduced at 600 kg ha^?1 but not at lower rates when compared to zero rate and it was negatively correlated with leaf N, P, and zinc (Zn) concentrations. Leaf N concentrations were significantly increased at 200 kg ha^?1 in five genotypes and at 600 kg ha^?1 in two genotypes compared to zero application. Leaf P and K concentrations were decreased with the application of fertilizer in most of the genotypes. The NPK fertilizer of 15-15-15 at the rate of 200–400 kg ha^?1 gave yield response in eight genotypes of D. rotundata, with minimal or no effect on their AM colonization when compared to zero application. Long term study on the effect of fertilizer application on AM symbiosis in yam is recommended.     

Systematic Measurement Methods for the Determination of the SPAD Values of Maize (Zea mays L.) Canopy and Potato (Solanum tuberosum L.)

Based on Soil Plant Analysis Development (SPAD) values, nitrogen (N) deficiency, nutrient need, and the effect of fertilizer treatments on crop conditions can be quickly estimated, but the method of SPAD measurement significantly affects the accuracy of estimation. In field experiments near Debrecen, Hungary, we measured the reliability and accuracy of SPAD measurements in maize and potato populations using a Minolta SPAD-502 meter (Minolta, Tokyo, Japan). The aim of our study was to determine which SPAD measurement methods are capable of detecting small differences in the SPAD values. During the examination of maize ear leaves, we determined the distribution of SPAD values along the leaf blade and then identified single- and multipoint measurement methods. By comparing the results of the measurement methods we established that the single-point-based measurements are less suitable for the determination of the average SPAD value of the leaf blade than the multipoint-based measurements. Also, we showed that the increase in the number of measurement points does not influence the accuracy of the measurement in the case of systematic measurement methods based on the distribution of SPAD values. Thus we recommend five-point measurements to obtain the average SPAD values of the ear leaves: the tip of the leaf blade and at one quarter and one half of the leaf blade from the base on both the right and left sides. From the measurements conducted in potato, we showed that the SPAD values change at every foliar level and that the measurements carried out on the middle foliar level provide the closest correlation with the average SPAD values of the leaf canopy. Based on these results, we recommend making measurements at different foliar levels or on the middle foliar level to determine the average SPAD value of the potato leaf canopy.     

Agronomic assessment of phosphorus efficacy for potato (Solanum tuberosum L) under legume intercrops

Abstract

Phosphorus (P) is an essential element and its efficient use is of global importance. This study evaluated the effect of growing potato under legume intercrops on P uptake and use efficiency indices: P harvest index (PHI), P uptake efficiency (PuPE), P partial factor productivity (PPFP) and P partial balance (PPB). The experiment was carried out for four consecutive seasons with treatments comprising potato cultivated under legume intercrops: none (T1), dolichos (Lablab purpureus L) (T2), peas (Pisum sativum L) (T3) and beans (Phaseolus vulgaris L) (T4). Across the seasons, the mean haulm P uptake for T2 (6.7?kg P ha^?1), T4 (5.5) and T3 (4.5) were 6%, 23% and 36% lower than that observed in T1 (7.1?kg P ha^?1), respectively. On the other hand, tuber P uptake was highest in T1 (21.8?kg P ha^?1) and T2 (21.3?kg P ha^?1) and were significantly higher than 13.2?kg P ha^?1 in T3 and 15.1?kg P ha^?1 in T4. This had a profound effect on PuPE, which was equally highest in T1 (0.26?kg total P uptake kg^?1 P supply) and T2 (0.25) and lowest in T3 (0.16) and T4 (0.18). Similarly, PPFP, PHI and PPB followed a similar trend, with highest values in T1 (57?kg tuber dry matter yield kg^?1 P supply, 76.4?kg tuber P uptake kg^?1 total plant’s P uptake and 0.20?kg tuber P uptake kg^?1 P supply, respectively). Among the tested legume intercrops, dolichos competed least for P with the main crop (potato) hence it can be integrated into potato-based cropping systems without compromising potato tuber yield.     

Boron fertilization effects in processing grade potato on an Inceptisol of West Bengal,India

A 2-year field trial was conducted in processing grade potato cv. Kufri Chipsona-3. The treatments comprised recommended dose of fertilizer (RDF) (200:150:150 N:P₂O₅:K₂O kg ha^?1) with or without boron (B) application (soil and foliar). The results revealed that B fertilization significantly increased tuber number and yield. Three sprays of 0.1% boric acid (at 40, 50 and 60 days after planting) produced the maximum number and yield of tubers and enhanced B uptake in potato tuber, haulm as well as in total plant accounting 85.8, 182.0 and 169.8% more than control, respectively. The same treatment came up with greatest net return and benefit: cost ratio. B fertilization exerted significant influence on available N and B status of post-harvest soil, while the effect was non-significant on available P and K. Results suggest that right dose and method of B application is vital for optimizing tuber yield and B-use efficiency for processing grade potato.     

Integrated nutrient management (INM) on yield trends and sustainability,nutrient balance and soil fertility in a long-term (30 years) rice-wheat system in the Indo-Gangetic plains of India

We analyzed data from a long-term rice–wheat cropping sequence to evaluate the effects of integrated nutrient management (INM) on yield trends and sustainability, nutrient balance and soil fertility of the system. After 30th cycle, grain yield of both the crops significantly declined under control and highest rice and wheat grain yields were obtained when 50% N supplied through green manure and farm yard manure, respectively. The magnitude of yield slope under INM was found considerably higher than 100% recommended fertilizer (RDF). Sustainable yield index (SYI) for both the crops were found lower in control but considerably higher with the 100% RDF and under INM. The soils under all the treatments suffered an apparent loss of K and N (except where organics replacing 50% N). Correlation study also reveals K is the sole factor for the yield sustainability as apparent K balance was negatively correlated with SYI and yield slope.     

腰果树体养分分布特征及其再吸收效率

以5个8龄腰果品系为对象,研究了腰果树体养分分布特征、品系间差异以及元素间相关性;并以无性系FL30为对象,研究了腰果树养分再吸收规律。试验结果表明,N、K、Ca、Mg、Mn主要存在于腰果叶片中,P、Cu主要分布于枝条和根系中,Fe、B则主要分布于根系中,Zn在叶、枝、根中分布较均匀。不同品系腰果树体养分分布特征存在一定的差异。腰果树体中养分元素之间存在一定的作用和影响,叶片中的Ca、Mn、B彼此之间以及N-P、Mg-Mn之间呈极显著的正相关关系,N-K、P-K、Cu-K、Zn-Cu之间呈显著的正相关关系;枝条中的N、P、K彼此之间以及Ca-B、Mg-B、Ca-Mn、Fe-Zn之间呈显著的正相关关系;根系中N-K、Ca-K、B-K、Fe-Zn之间呈极显著的正相关关系,N-B、Ca-B以及K-Zn之间呈显著的正相关关系。腰果树N、P、K再吸收效率较高,Cu、Zn再吸收效率较低;Ca、Mg、Fe、Mn、B在衰老叶片中富集,其中Mn的富集程度最高,其次是Ca>B>Mg,Fe的富集程度最低。     

Boron Fertilization in Sunflower (Helianthus annuus L.) in an Inceptisol of West Bengal,India

This study is a synthesis of information on growth, yield, and boron-use efficiency of hybrid sunflower (cultivar Aditya) in an inceptisol (Gangetic alluvium) of West Bengal, India, under varied proportions of soil and foliar-applied boron. Foliar spray of boron (B), under all circumstances, performed better than soil application of B fertilizers with regard to sunflower seed and total dry-matter yield, B uptake, and B-use efficiencies, while 0.2 percent foliar B spray was associated with greatest B recoveries, B-use efficiencies, and sunflower seed yields in the experimental years.     

栽培模式对直播油菜生长、产量和养分吸收利用的影响

发展直播油菜对增加我国油菜种植面积和总产有重要意义,但栽培措施尤其是施肥技术的滞后极大地影响了油菜的产量及施肥效果。2009/2010年度在湖北省油菜主产区设置田间试验,研究栽培模式对直播油菜生长、产量、经济效益和养分吸收利用的影响,探讨适合当前生产的高产高效栽培技术。结果表明,各优化模式比农民习惯栽培模式均有增产增收效果,其中在30104 plant/hm2种植密度、秸秆还田和加强病虫草害防治的基础上进行优化施肥（氮、磷、钾肥用量分别为N 195 kg/hm2、 P2O5 90 kg/hm2、K2O 90 kg/hm2,硼砂用量15 kg/hm2,氮肥和钾肥分次施用）的模式Ⅲ表现最好,比农民习惯施肥增产35.9 %、增收1632 Yuan/hm2,地上部干物质量和养分累积也均较高,氮、钾肥偏生产力分别为N 13.7 kg/kg和K2O 29.8 kg/kg,实现高产高效目标。说明当前直播油菜的栽培模式应结合其生长发育进程和养分吸收规律,适当密植以增库促源,加强植保防治病虫草害,更重要的是积极推行平衡施肥和有机、无机配施,并合理安排施肥时期及比例。