Number Of Tubers Research Articles

Response of potato tuber as an effect of the N-fertilizer and paclobutrazol application in medium altitude

Abstract Development of G0 potato seeds in medium altitude with high temperatures has been constrained high temperatures, which inhibited plant growth and development, especially for tuber formation. The production of G0 potato seeds in the high-temperature area can be increased by the application of nitrogen (N) fertilizer and paclobutrazol (PBZ). The study aimed to identify the effect of different doses of N-fertilizer and the frequency of PBZ application on the plant growth and yield of first-generation potato seeds (G0) in medium land. The Randomized Complete Block Design with two factors was used in this experiment. The first factor was the dose of N-fertilizer (n 1 = 60, n 2 = 120, and n 3 = 180 kg/ha) and the second factor was the frequency of PBZ application (p 1 = 1, p 2 = 2, and p 3 = 3 times), applied starting at 40 DAP and repeated every 10 days with a concentration of 100 ppm. The results showed that there was a significant interaction between the dose of N-fertilizer and the frequency of PBZ application on plant dry weight. The 120 kg/ha of N-fertilizer-treated plants exhibited the highest plant height and the number of stolons per plant, whereas three times PBZ application treated plant exhibited the higher tuber growth rate, the number, and weight of tuber per plant with the value of number and weight of tuber per plant of 9.26 and 83.97 g, respectively. It can be concluded that N-fertilizer increased plant growth, whereas PBZ increased G0 potato seeds in the medium land altitude with high temperature.

The Effect of Alternative Tillage Practices on Potato Growth and Yield

An experiment was conducted during the rabi seasons of 2021-22 and 2022-23 at the Research Farm, ICAR-Central Potato Research Station RS, Gwalior (M.P.). The experiment consisted of 7 treatments viz.; Farmer’s practice (T1), CIP Technique (T2), Regional AICRIP/INSTITUTE recommendation/hoeing (T3), Flat-bed planting (T4), Flat-bed planting & mulching (T5), Flat-bed planting & ridging (T6) and Flat-bed planting, ridging and mulching (T7) with 3 replications. The soil of experimental field was a sandy clay loam with uniform topography. The result showed that CIP Technique (T2) at par with Flat-bed planting, ridging and mulching (T7) were registered superior values of growth parameters viz.; plant height, number of compound leaves per plant and dry weight of haulm per plant (45.67 & 45.43 cm, 49.38 & 49.10 and 24.73 & 24.00 g; respectively), yield attributes viz.; number of tubers per plant and dry weight of tubers per plant (8.72 & 8.65 and 54.97 & 54.50 g; respectively) as well as tuber yield (299.23 & 282.44 qha-1) of potato over rest of the treatments.

Effect of Different Levels of Nitrogen and Potassium on Yield and Quality of Potato

The research experiment was carried out at Nalanda College of Horticulture, Noorsarai during 2021-22 to find out the effect of different levels of nitrogen and potassium on the growth and yield of potatoes. Findings of research showed that among the individual nitrogen and potassium levels, N5 and K4 performed better in respect of, the number of tubers per plant (7.85 and 6.80), average tuber weight (62.28 g and 67.27 g), tuber weight per plant (656.71 g and 473.45 g), tuber yield (270.95 q/ha and 216.73 q/ha), the diameter of tuber (5.21 cm and 3.98 cm), vitamin C content in tuber (14.15 mg/100gm and 11.89 mg/100gm), fresh weight (63.68 and 109.79), dry weight (12.89 and 22.12), moisture content of fresh tuber (76.09 and 91.07). In the case of interaction effect of N×K, the treatment of N5×K4 pronounced significantly to the number of tubers per plant (11.44), single tuber weight (110.19 g), plant tuber weight (962.00 g), tuber yield (360 q/ha), diameter of tuber (8.10 cm), vitamin C content in tuber (18.50 mg/100 g), fresh weight (109.79 g), dry weight (22.12 g), moisture content of fresh tuber (91.07 g). Potato var. Kufri Lima yielded the maximum (360.76 q/ha) in the interaction of N5×K4 when applied with 160 kg/ha nitrogen and 120 kg/ha potassium.

Influence of improving selections on potato productivity in original seed nurseries in Karelia conditions

In potato seed production, selections contribute to maintaining varietal typicality, increasing yields and improving the quality of seed material. The purpose of this work is to evaluate the effectiveness of improving selections in the first field generation of potatoes under conditions of variability of meteorological factors during the growing season of plants. In the process of crop reproduction, the yield indicators of the super-super elite of three varieties of the early ripeness group (Latona, Impala, Red Scarlett) are reflected during the selection in the first field generation. Using cluster and step-by-step discriminant analyses, three groups of productivity of vegetative offspring were identified for each of the above varieties: I – maximum, II – average, III – minimum. In the experiment, they were used as experimental options for control – offspring without selection. Against the background of the absence of reliable deviations in the number and weight of tubers in the experimental variants from the corresponding controls, a tendency to increase production was revealed.

Respon Pertumbuhan dan Produksi Bawang Merah (Allium ascalonium L.) Terhadap Pupuk NPK

North Sumatra is shallots. Shallot (Allium ascolonicum L.) is a horticulture that has many benefits for people's lives, both from economic value and nutritional content, so that shallot production increases every year and is proven based on BPS (Central Statistics Agency) for the last 5 years. The effort needed to meet the needs of shallot production is to increase soil productivity, using the addition of NPK fertilizer. This study used factorial randomized group design (RAK). For accuracy in this study, it was repeated 3 times. namely: NPK fertilizer (N) with 3 levels, namely: N0 = Control, N1 = 5 g/plant, and N2 = 10 g/plant. The results of the Anova Variance test showed that the response of NPK fertilizer treatment to plant height 3 mst, 4 mst, 5 mst, 6 mst and wet weight of tubers per plot (g) had a significant effect, but the observation of the number of tubers per sample plant (tubers), and the diameter of tubers per sample (mm) had no significant effect. Keywords: NPK fertilizer, NPK dosage, and shallots

Using Biochar to Improve Soil Fertility and Productivity of Drought-Tolerant Sweet Potatoes in Thanh Hoa Coastal Sandy Soil

The coastal area of Thanh Hoa province has a large proportion of sandy soil and is suffering negative impacts from climate change that affect crop productivity. The aim of this study is to investigate the use of biochar to improve the soil fertility and productivity of drought-tolerant sweet potatoes. The effect of biochar contents on the productivity of three sweet potatoes VC 04-24, KL C3, and VC 68-2 in the coastal sandy soil area of Thanh Hoa province was examined. The results indicated that the yield of sweet potatoes was the highest when applying five tons of biochar per hectare, equivalent to using 10 tons of manure. With the same biochar content, the productivity and other factors related to the product quality of these sweet potatoes such as the number of tubers per plant and the average mass of tuber were the highest. In detail, the estimated commercial productivity of VC 04-24, KL C3, and VC 68-2 were 25.46, 24.92, and 21.76 ton/ha, respectively. With the least significant difference at the probability of 0.05% (LSD0.05), the VC 04-24 and KL C3 showed high productivity. The economic efficiency of the sweet potatoes-growing model at Hai An commune, Tinh Gia district, Thanh Hoa province showed that the productivity of the model was 24 tons/ha, higher than the actual productivity of the control model (20.2 ton/ha). The productivity and the economic efficiency of the model were 18.8% and 31.38% higher than those of the control model, respectively. In addition, the test results showed that using 5-6 ton/hectare of biochar can improve the physical and chemical properties of soils.

Pengaruh Pemberian Pupuk NPK dan Media Arang Sekam Terhadap Pertumbuhan dan Produksi Bawang Merah (Allium cepa L.)

Shallots are known as a type of spice for food flavoring and also as a traditional medicine whose benefits have been felt by the wider community. The production of shallots in Sijunjung Regency has not shown optimal results even though NPK fertilizers have been used. To overcome this, it is necessary to add organic fertilizers such as husk charcoal. This study aims to determine the effect of the growth and production of Allium cepa (L.) shallots on the combination of applying npk fertilizer and husk charcoal.The research was in the form of an experiment using a complete randomized design (RAL) with five treatments and four replicates. P0 treatment (NPK 0g/polybag + husk charcoal 0g/polybag), P1 treatment (NPK 1.25g/polybag x 8 + husk charcoal 80g/polybag), P2 treatment (NPK 1.30g/polybag x 8 + husk charcoal 90g/polybag), P3 treatment (NPK 1.35g/polybag x 8 + husk charcoal 100g/polybag), P4 treatment (NPK 1.40g/polybag x 8 + husk charcoal 110g/polybag). The variables observed were plant height, number of leaves per clump, number of tubers per clump, wet weight and dry weight. Furthermore, the data was analyzed using a variety of fingerprint analysis followed by a DMRT test with a level of 5% on data that had a real effect. The results showed that the combination of NPK fertilizer and husk charcoal had a real effect on the number of leaves per clump (P <0.05) and had no real effect on plant height, number of tubers per clump, wet weight and dry weight. The P4 treatment produced the highest number of leaves (34.50 leaves), while the highest number of bulbs was also achieved by the same treatment with an average of 8.75 bulbs per clump. The conclusion of the study results is Overall, the application of NPK and husk charcoal shows the potential for an increase in the number of leaves, but it is not significant in other aspects. Keyword: shallots, husk charcoal, NPK, growth, production

Spatial distribution and impacts of microplastics on potato growth and yield in agroecosystems in Sialkot, Pakistan

Microplastic (MP) pollution is a growing concern, yet its impacts on agroecosystems remain poorly understood. This study investigates MP contamination in the agroecosystems of Sialkot, Pakistan, and its potential effects on the growth, physio-biochemical attributes, and yield of potato (Solanum tuberosum L.). Plant and soil samples from 10 diverse agricultural fields were collected and analyzed for MP contamination. FTIR analysis revealed widespread MP presence in the soil across all sites. Fragment, film, and fiber types dominated, with low-density polyethylene (22.42 %), high-density polyethylene (18.05 %), and polystyrene (12.3 %) being the most prevalent polymers. A significant variation in plant growth parameters was observed. The number of tubers per plant also exhibited a significant difference, as evidenced by the decline in potato yield with increasing levels of MP contamination. Potato yield showed a negative correlation with MP contamination levels. The nutrients (Zn, Cu, Ni, and Na) uptake in plant shoots was also observed to be decreased except for Mg and Mn at all sites. This study showed that MPs are contaminating our agricultural lands and they may affect growth and yield of potato. Additional research is needed to understand the underlying mechanisms and develop mitigation strategies to improve agricultural productivity and food security.

Potato–Soybean Intercropping Increased Equivalent Tuber Yield by Improving Rhizosphere Soil Quality, Root Growth, and Plant Physiology of Potato

Potato–legume intercropping has been confirmed to increase productivity in modern agricultural systems. However, the physiological and ecological mechanisms of potato–soybean intercropping for promoting tuber yield formation in potato remain unclear. Field experiments were conducted in 2022 and 2023 to explore the responses of tuber yield formation, rhizosphere soil quality, root growth, and plant physiology of potato in potato–soybean intercropping. The soil at the experimental site is Cambisols. The treatments included sole cropping potato, sole cropping soybean, and potato–soybean intercropping. Our results indicated that potato –soybean intercropping decreased the water content, increased the total K content and activities of urease and catalase in rhizosphere soil, and enhanced the root mean diameter, root projected area, and root length density in the 0–5 cm and 15–20 cm soil layers of potato. Moreover, potato–soybean intercropping improved the plant photosynthetically active radiation and light transmittance rate of the middle and lower layers as well as the leaf area index, enhanced the leaf chlorophyll b content and ribulose-1,5-diphosphate carboxylase/oxygenase activity, and increased the leaf net photosynthetic rate and organ dry matter accumulation amounts of potato. The changes in the above parameters resulted in an increased tuber weight per plant (19.4%) and commercial tuber number (42.5%) and then enhanced the equivalent tuber yield of potato (38.2%) and land equivalent ratio (1.31 in 2022 and 1.33 in 2023). Overall, potato–soybean intercropping greatly increased the equivalent tuber yield by improving the rhizosphere soil quality, root growth, and plant physiology of potato and then achieved a higher land equivalent ratio.

Effects of subsurface drip fertigation on potato growth, yield, and soil moisture dynamics

AimsThis study aimed to evaluate the impact of subsurface drip fertigation (SDF) on soil moisture content, potato growth, and tuber yield in loam soils, and compare these results with conventional surface drip fertigation (CF). The focus was on determining whether SDF could improve water use efficiency and yield quality, particularly in water-scarce regions.MethodsThe experiment was conducted during the 2022 spring growing season in Xunyang, Ankang, Shaanxi Province, China. A randomized complete block design (RCBD) was used with three treatments: subsurface drip fertigation (SDF), conventional surface drip fertigation (CF), and a no-fertilization control (NF), with four replications per treatment. Soil moisture content at a 20 cm depth was monitored, and plant growth parameters such as plant height, stem diameter, leaf color index, and chlorophyll fluorescence index were measured during the flowering and harvest stages. Tuber yield characteristics, including tuber diameter, number of tubers per plant, total yield, and marketable yield, were also assessed.Important findingsThe results indicated that subsurface drip fertigation significantly improved soil moisture content, with up to 45.5% higher moisture retention compared to conventional fertigation, particularly in the early stages of fertilization. This improved moisture availability led to enhanced plant growth and tuber development. Tuber diameter increased by 6.9 mm, and the number of tubers per plant increased by 18.1% under SDF. Marketable tuber yield was approximately 10% higher in the SDF treatment compared to CF. However, the study found that soil texture plays a critical role in the effectiveness of SDF, and further research is needed to explore its application in other soil types.

The Effect of Nitrogen and Potassium Interaction on the Leaf Physiological Characteristics, Yield, and Quality of Sweet Potato

This study selected two sweet potato varieties as research subjects and conducted a field experiment using a two-factor design with two potassium (K) levels (K0 and K1) and five nitrogen (N) levels (N0–N4). The physiological changes in sweet potato leaves under different N and K treatments were measured, and nutrients such as the soluble sugar, protein, and starch content of sweet potato roots were analyzed. The results indicate that the activity of glutamine synthetase (GS) and the soluble protein content in sweet potato leaves increase first and then decrease with increasing N application, while K application can significantly increase the activity of GS and the soluble protein content. The N metabolic capacity of leaves is strongest when the fertilizer ratio is K1N2. The SPAD value of sweet potato leaves increases with increasing N application. The net photosynthetic rate, stomatal conductance, and intercellular CO2 concentration first increase and then decrease with increasing N application. K fertilizer has a significant effect on these parameters. As the N application rate increases, the starch and protein content in the tubers increase, while the soluble sugar content decreases. However, the number of tubers per plant, fresh weight of the tubers, and dry weight of the tubers increase initially and then decrease, while the vine length continuously increases. The application of K fertilizer can significantly increase the number of tubers per plant and stem thickness of sweet potato. In conclusion, the appropriate N–K combined application can promote N metabolism, enhance the photosynthetic capacity of sweet potato, increase yield, and improve quality.

Fertilizer management practices for cassava in acid dryland of Sukabumi Regency, West Java

The productivity of cassava in acid dryland is generally still low. Fertilization, land amelioration, and superior varieties are the main solutions for increasing cassava productivity. This research aimed to determine the response of high-yielding varieties and fertilization technology packages to the growth and yield of cassava in acid dryland of Sukaharja Village, Warung Kiara District, Sukabumi Regency, West Java. The contents of organic carbon, nitrogen, and magnesium of the soil is below the minimum threshold, so the application of N fertilizer, organic matter, and ameliorant is expected to increase plant growth. The research consisted of two treatment factors: two cassava varieties and three fertilization technologies. The treatments were arranged in a completely randomized split-plot experimental design with three replications with variety as the main plot and fertilization technology package as the subplots. The treatment effect was observed on the character of plant height, wet biomass weight, stem diameter, number of tubers, tuber length, tuber diameter, tuber weight (large and small) per plant, and tuber yield per plot to be converted per ha. Tuber quality was observed by observing water content, percent dry matter, and starch yield. The results showed that the fertilization technology package increased plant height, fresh biomass weight, stem diameter, large tuber weight per plant, and yield per hectare in both varieties. Differences in varieties and fertilization technology packages have no effect on starch levels.

Increasing Production Of Purple Sweet Potato (Ipomoea Batatas Poir) By Treatment Of Shimmer Fertilizer and Kaliphos

The title of the research was “Increased Production of Purple Sweet Potato (Ipomoea batatas poir) with Vermicompost and Kaliphos Fertilizer Treatment”. This research was carried out for 4 months in the experimental garden of the Faculty of Agriculture, Islamic University of Riau. The purpose of this study was to determine the effect of interaction and the main effect of increasing purple sweet potato production by the treatment of vermicompost and Kaliphos fertilizer. The design used was a completely randomized factorial design consisting of two factors. The first factor was vermicompost fertilizer (K) with 4 levels: 0. 550. 1.100. 1,650 g/bundle. The second factor is Kaliphos fertilizer: 0.5. 10. 15 g/plant. Parameters observed were the number of tubers per plant (fruit), tuber weight per tuber (g), tuber weight per plant (kg), tuber production per mound (kg), harvest index, and fresh chestnut weight per plant (kg). The last observational data were analyzed statistically and continued with the BNJ follow-up test at level 5 %. The results of the study conclude that the interaction effect of vermicompost and caliphos fertilizer is significant on tuber weight per tuber, tuber weight per plant, tuber production per mound, harvest index, and fresh chestnut weight per plant. The best treatment dose was 1,650 g/mound and Kaliphos 15 g/plant (K3L3). The main effect of vermicompost fertilizer is real in all treatments. The best treatment dose is 1,650 g/mound (K3). The main effect of caliphos fertilizer is significant for all treatments. The best treatment dose is 15 g/plant (L3).

Optimization of vine killing date for maximum seed-tuber yield and minimum exposure to late-season aphid vectors in potato

Short-duration and early-bulking potato varieties are well-suited for commercial cultivation in the subtropical Indo-Gangetic plains of India. To maximize seed tuber yield, prevent late-season exposure to aphid vectors, and facilitate the timely planting of wheat crops during the rabi season, it is essential to cut the haulms (vines) of seed potatoes at the earliest possible time. A study was conducted to standardize the optimal vine-killing date for two popular potato varieties in the north-western plains of India, Kufri Pukhraj and Kufri Jyoti, by examining variations in seed yield across different vine-killing dates and assessing the incidence of aphid vectors transmitting potato viruses. Tubers were planted on 15 October for two consecutive seasons, and haulms were cut at 70, 80, and 90 days after planting (DAP), with continuous monitoring of aphid populations. Results showed that total tuber yield and tuber numbers increased with delayed vine-killing. Similarly, the yield and number of oversized tubers significantly rose as the vine-killing date was extended. However, seed-size and undersized tuber yields were largely unaffected, while the number of undersized tubers decreased between 70 and 90 DAP. Further, the gain in total tuber yield and yield of over-sized tubers occurred mainly during 70–80 DAP for Kufri Pukhraj in contrast to Kufri Jyoti where maximum increase occurred between 80 and 90 DAP. Therefore, it is concluded that the optimum time of vine killing for maximum seed tuber yield is directly linked to the tuber growth cycle of individual variety. The period of maximum incidence of aphid vectors varied between the two years. Based on the incidence of Myzus persicae, the seed crops in north-western plains of India should not be extended beyond last week of December although real time monitoring of the aphid incidence is recommended.

Agronomic dataset on potato growth and yield in the Netherlands

Data was collected at two field locations in the Netherlands: on the clayey soils in Lelystad and the sandy soils of Vredepeel during 2019 and 2020. The original aim of this dataset was to calibrate and evaluate crop growth models for estimating potential, water-limited and nitrogen-limited yield levels for modern potato cultivars. Therefore, treatments include different cultivars, irrigation regimes, nitrogen fertilization, and light interception. During the two seasons extensive data was collected either passively, via non-destructive or via destructive measurements. Passive measurements consisted of weather and soil moisture data and were taken continuously throughout the season. Non-destructive data was collected on photosynthesis, reflection/light intensity, SPAD chlorophyll values, plant height, crop phenology, and groundwater level roughly every other week throughout the seasons. Destructive measurements were taken on biomass (leaves, stems and tubers), leaf area, NPK content (leaves), and the number of tubers between five and seven times per season. Additionally, during the final harvest data was collected on the tuber size distribution, marketability, and NPK content of the tubers.

Cortical Gyrification Is Associated With the Clinical Phenotype in Tuberous Sclerosis Complex

BackgroundTuberous sclerosis complex (TSC) is characterized by cortical tubers, determining cortical disarrangement and consequently drug-resistant epilepsy, intellectual disability, and TSC-associated neuropsychiatric disorders (TAND). Aim of the studyTo establish whether gyrification index (GI), a software-based neuroradiological parameter, could be associated with the severity of phenotype in TSC, identifying the cortical regions that are more associated with the severity of the main clinical manifestations. MethodsThis was a retrospective cross-sectional study. Magnetic resonance imaging was acquired on a 1.5-T scanner. CAT12 toolbox was used for the estimation of GI. Data analysis was performed with Jamovi. The level of significance was set to P < 0.05 for all tests. ResultsForty-five patients with TSC and 42 healthy controls were included. Patients with TSC were characterized by higher total GI (P = 0.002) compared with healthy controls. Among patients with TSC, a higher total GI was associated with impaired neurological examination (P = 0.039), epilepsy (P = 0.017), intellectual disability (P = 0.013), TAND (P = 0.013), and higher number of cortical tubers (P < 0.001). An increased local GI in specific cortical areas was associated with TAND and autism spectrum disorders. ConclusionsGI is a software-based neuroradiological parameter that could represent a reliable overall prognostic marker in TSC. Local GI can be used to identify phenotype-specific gyrification patterns allowing an early characterization of patients with TSC.

Effects of Planting Date and Field Type outweighed the Effect of Seed Origin on Ware Potato Yield

AbstractPotato yields in the Netherlands are highly variable. Although variability in yield has previously been attributed to several crop management factors, part of the variability remains unexplained. It is hypothesized that part of this unexplained yield variability is influenced by seed potato origin, encompassing where and under what conditions seed potatoes have been cultivated. In this study, we investigated the effect of seed potato origin on crop characteristics and tuber yield in interaction with and in comparison to planting date and field type in a two-year on-farm experiment on a large-scale potato farm. We evaluated three different seed potato origins of the variety Fontane, three different planting dates (early, intermediate, late), and two different field types (wet rainfed and dry irrigated). Origin significantly affected the number of stems per plant and the number of tubers per stem in both years. This resulted in a significant effect of origin on the number of tubers per plant in the first year. In that year, the origin with the lowest number of tubers per plant also produced the highest yield of tubers larger than 50 mm. Despite these (small) effects of seed potato origin on crop characteristics, origin did not significantly affect gross and marketable yield. Moreover, there was no interaction between origin and planting date and/or field type. However, planting date and field type had a significant effect on yield. Ware potato yield in the wet rainfed field was up to 17 t ha−1 higher than in the dry irrigated field, and late planting resulted in a yield reduction of up to 10 t ha−1. We conclude that for maximizing ware potato yield of the variety Fontane in the Netherlands, the effects of planting date and field type outweighed the effects of seed tuber origin.

Effect of Chemical Pesticides on the Growth and Yield of Two Industrial Potato Varieties (Asterix and Courage) in Bangladesh

Experiments were conducted to find out suitable disease management practices to produce quality potato seeds in processing the varieties of Asterix and Courage in Bangladesh. A set of two field experiments was conducted in two different Agroecological zones of Bangladesh. A Factorial Randomized Completely Block Design with 2 potato varieties, 4 treatments, and 4 replications for each were used. A significant difference was found in the plant height and number of tubers per hill. In contrast, days to tuberization and the number of stems per hill of both varieties in response to pesticide application were insignificant. The highest tuber yield and better A and B-grade tubers were recorded, in which fungicides and insecticides were applied. The primary viral infection had been identified in the control and fungicide-treated plots only while there was no viral disease incidence was observed in the insecticide-treated plots. The incidence of post-harvest disease and disorder was found to be negligible. J. Bio-Sci. 32(2): 13-22, 2024

SEED POTATO PRODUCTIVITY AS INFLUENCED BY ELECTRICAL CONDUCTIVITY OF THE NUTRIENT SOLUTION IN SOILLESS MEDIA DURING SPRING SEASON IN SUBTROPICAL REGIONS OF N- W INDIA

Soilless cultivation under controlled conditions is used for rapid multiplication of early generation virus-free potato seed using aeroponics and other mediums. The plant growth under these systems is affected by different factors like soilless media, nutrient solution concentration used, environment, genotype etc. Besides the composition of nutrient solution its electrical conductivity (EC) influences availability of nutrients and affects plant growth and yield. The two-factorial study on water source and EC was carried out on a cocopeat based medium for a nutrient efficient variety Kufri Gaurav. Well sprouted aeroponically produced minitubers of the variety were planted (at 30 x 15 cm planting density) in soilless medium filled troughs placed under net house. The water source Normal tap water was compared with RO (demineralized) water, while EC was considered at three levels 1.0, 1.5 and 2.0. The results indicated a proficient growth of the genotype at EC 2.0 (plant height, number of leaves, stem diameter, leaf length and number of stems). However, for the yield characters, EC 1.0 was found to produce both higher number of tubers, yield as well as harvest index per meter square. Based on the observations it can be inferred that at lower EC the partitioning of the photosynthates is towards the sink (tubers) as compared to the vegetative growth, which would be more desirable under the soilless systems, where limited/ managed canopy growth is more desirable, with higher productivity. The study also indicated virus free seed production in soilless medium during the spring season (seed plot period lasts up to December) in northwestern plains of India under net house, giving indication for successive/ multiple seed crops under soilless controlled conditions.

EFFECT OF IRRIGATION METHODS AND NUTRIENT MANAGEMENT PRACTICES ON PRODUCTION AND ECONOMICS OF POTATO UNDER DIFFERENT PRECEDING CROP SEQUENCES IN CENTRAL INDIA

A field experiment was conducted at ICAR-Central Potato Research Institute-RS, Gwalior, in split-plot design: 3 irrigation methods (main plots) and 5 fertilizer doses in various crop sequences (sub-plots), with four replications. Results revealed that the highest total tuber number (604 thousand/ha) was recorded with dhaincha - potato (75% RDF NPK) which was significantly higher than all other treatments except green gram - potato (75% RDF NPK). Drip irrigation resulted in highest total tuber yield (35.8 t/ha), significantly surpassing other methods. Dhaincha - potato (75% RDF NPK) combination yielded (37.5 t/ha) highest, significantly outperforming others except fallow - potato (50% RDF NPK/ha + 15 t FYM) sequence. Drip irrigation x fallow - potato (50% RDF NPK/ha + 15 t FYM) combination recorded the highest total tuber yield at 40.3 t/ha. Drip irrigation resulted in water-use efficiency of 137 kg/ha-mm and harvest index of 72%, significantly surpassing other methods. Fallow – potato {FYM 7.5 t/ha + crop residue 7.5 t/ha + biofertilizers (Azotobacter and PSB)} sequence recorded highest harvest index 73%, significantly surpassing other treatments. Drip irrigation resulted in highest WUE (137 kg/ha-mm), significantly surpassing other methods. Combination of drip irrigation x fallow – potato (FYM 7.5 t/ha + 50% RDF NPK) sequence recorded highest WUE (155 kg tuber/ha-mm), significantly outperforming other treatments. Dhaincha – potato (75% RDF NPK) sequence resulted in the highest nitrogen content (216 kg/ha), significantly surpassing others. Dhaincha - potato (75% RDF NPK) sequence significantly out performed in tuber nitrogen uptake (77 kg/ha) to other sequences. Combination of drip irrigation x dhaincha - potato (75% RDF NPK) sequence recorded highest N uptake (83 kg/ha). Benefit : cost was highest with drip irrigation (3.1) among irrigation methods and it was highest with dhaincha - potato (75% RDF NPK) sequence (2.99) among crop sequences.