Open Access Original Research Article

Response of Potato Crop to Integrated Nutrient Management in the Indo-Gangetic Alluvial Soils of West Bengal, India

Shubhadip Dasgupta, Arindam Sarkar, A. Krishna Chaitanya, Aritra Saha, Arup Dey, Riasen Mondal

Journal of Experimental Agriculture International, Page 1-10
DOI: 10.9734/JEAI/2017/33138

A field experiment was carried out to investigate the influence of Integrated Nutrient Management (INM) on nutrient uptake and yield of potato (Solanum tuberosum L.) in the Gangetic alluvium belt of West Bengal during two consecutive years i.e. 2011-12 to 2012-13. The experiment was laid out in a randomized complete block design with three replications. Different levels and combinations of organic (crop residue, farm yard manure and bio-fertilizer) and chemical fertilizers were tested. Plots receiving only organic manures reported least amount of nutrient uptake (36.00-44.65, 7.57-11.0 and 44.66-72.66 kg·ha-1 for N, P and K respectively). The nutrient uptake was significantly higher when chemical fertilizers were applied. Maximum response was found (up-to 161, 221 and 354% increment for N, P and K respectively compared to control) when different sources were combined together. Strong correlation has been found between nutrient uptake, tuber dry weight, specific gravity, ascorbic acid and reducing sugar content suggesting role of nutrients uptake on tuber yield and quality. With increasing nutrient uptake, up to 80% increment in yield was found from those plots. It was noted from our experiment that sole use of organics was not effective enough for supplying nutrients. However, the integration of organic fertilizers with chemical ones had significantly improved soil and crop health, providing better crop yield and quality.

Open Access Original Research Article

Leaf Tip Die- Back of Yucca elephantipes by Lasidiplodia theobromae Pat. and Production of Phytotoxin in Filtrate and Infected Leaves

O. F. Aigbokhan, A. O. Claudius- Cole, B. Ikotun

Journal of Experimental Agriculture International, Page 1-8
DOI: 10.9734/JEAI/2017/31864

Aims: Leaf tip die-back is a foliar disease of Yucca elephantipes that significantly reduces its aesthetic value. Investigations were carried out on the pathogenicity of the causal organism. 

Methodology: A Bioassay of the isolated phytotoxin produced by the pathogen was carried

out on yucca, jatropha, cowpea and  maize. The isolated fungus was grown on Czapek- Dox liquid medium and mycelia were harvested by filtration at 7-day intervals for 49 days.  The filtrate was applied on leaves of test plants growing in pots arranged in Complete Randomized Design with four replicates.

Results: Lasiodiplodia theobromae was identified as responsible for the leaf tip die- back disease of yucca. Results of the pathogenicity test showed significant (p=.05) increase in the rate of development of necrosis and chlorosis with time. Significant increase in the necrotic and chlorotic lesions (p=.05) were observed among the test plants inoculated with 28, 35, 42, and 49 day old culture filtrate of Lasidioplodia theobromae. Extracts from infected leaves induced necrotic spots surrounded by a chlorotic halo ranging from 0.2- 1.2 cm. Evidence from this study demonstrated that L. theobromae is the causal organism of yucca leaf tip die back. The toxic principle can be isolated from 28 day-old cultures while the extract from infected yucca leaves produced all the symptoms as did the pathogen.

Open Access Original Research Article

Effects of NPK Fertilizer Application Rates and Intra-row Spacing on Yield of Radish (Raphanus sativus L.)

A. H. Umar, A. K. Ibrahim, I. Alhassan

Journal of Experimental Agriculture International, Page 1-6
DOI: 10.9734/JEAI/2017/33136

Field experiments were conducted during 2013 rainy season at the Kano State Institute of Horticulture Bagauda, Kano and Federal College of Horticulture Research and Training Farm Dadinkowa, Gombe State. The experiment investigated the effect of NPK fertilizer application rates and intra-row spacing on yield of radish (Raphanus sativus L.). The treatments were six level of NPK fertilizer (0, 40, 80, 120, 160 and 200 kg/ha) and three levels of spacing (10, 15 and 20 cm). The treatments were laid down in a randomized complete block design (RCBD). Yield and yield components were measured and data were analyzed using ANOVA. Intra-row spacing significantly affected root diameter and root length. The result of the study indicated that increasing level of NPK fertilizer from 0 to 200 kg/ha increased significantly yield components. Increasing intra-row spacing from 10 to 20 cm had produced significant increase in yield characters, including root yield in both locations. The significant interactions were recorded on yield characters such as root diameter and root length. Finally 120 kg with 20 cm intra-row spacing appeared optimum for good yield of radish.

Open Access Original Research Article

Effect of Soil and Foliar Nitrogen Application on Growth, Yield and Quality of Baby Corn Cultivars

M. P. Neupane, S. P. Singh, U. Sai Sravan, Abhishek Singh

Journal of Experimental Agriculture International,
DOI: 10.9734/JEAI/2017/32574

An imperative nitrogen management schedule attempted for the first time using soil application fb (followed by) foliar application at harvest stage to improve productivity and quality of baby corn. A two year study carried out in winter season with three cultivars and six schedules of recommended dose of nitrogen (RDN) application. Nitrogen scheduling in two, three and four splits compared on composite and hybrid cultivars. Crop growth, productivity traits, picking wise cob and corn yields, quality, plant nutrient ratios and nutrient harvest indices were determined. Cultivars followed the order HM-4>HQPM-1>Azad Uttam for yield components, yield and quality. HM-4 gave 7.0% and 31.6% higher mean baby corn yields than HQPM-1 and Azad Uttam. Soil fb foliar RDN application in 4 splits [50% as basal (B), 25% at knee height stage (KHS), 20% at tassel emergence (TE) fb 5% foliar spray after first picking (FSAFP)] recorded higher yield attributes, baby cob and corn yields, and quality. Cultivars and N application schedules influenced nutrient ratios. Nutrient harvest indices also varied in response to N application schedule. HM-4 can be cultivated with RDN (150 kg ha-1) in 4 splits (soil fb foliar) for attaining better yield and quality of winter baby corn. Further studies are required for better understanding of combined approach under diverse conditions.

Open Access Original Research Article

Physiological Responses to Drought Stress in Jatropha curcas Seedlings

N. Contran, L. Ledda, M. Mulas, R. Cerana, M. Lubino

Journal of Experimental Agriculture International, Page 1-13
DOI: 10.9734/jeai/2017/v16i3138

 

Aims: The aim of the study was to investigate the physiological mechanisms of Jatropha curcas seedlings exposed to drought and the possible influence of seedling age.

Study Design: A pot experiment was carried out using a completely randomized design with two seedling ages (2- and 3-month-old seedlings), two treatments per age (Watered: fully irrigated, and Unwatered: Not irrigated), six replicates (24 pots).

Place and Duration of Study: The experiment was performed in a greenhouse facility located at the Experimental Station “Mauro Deidda” (Department of Agriculture of University of Sassari) at Ottava (Sassari, Italy) between June and September 2011.

Methodology: To investigate the responses of 2- and 3-month-old J. curcas seedlings exposed to drought stress on 4th, 8th, 12th, 19th, and 26th day from treatment’s beginning, leaf and soil water content, biometric, gas exchange, and chlorophyll a fluorescence measurements were performed; on 26th day from treatment’s beginning, biometric destructive measurements were carried out.

Results: Results support the hypothesis that J. curcas is appropriate to be cultivated in areas with limited water availability or prolonged periods of drought and highlight that mechanisms of drought response are highly influenced by seedling age. J. curcas seedlings maintained a good leaf water status by means of an effective stomatal closure, associated with a reduced aboveground growth and an increased root:shoot ratio. Under drought stress, 2-month seedlings showed a higher allocation of resources to roots compared to 3-month seedlings. Drought resulted in more detrimental effects on the photosynthetic response of 3-month seedlings, inducing the reduction of stomata conductance and the loss of photosystem II integrity. 2-month seedlings were instead able to activate mechanisms of drought tolerance through the activation of excess energy dissipation mechanisms.

Conclusion: In the early stage of crop establishment, the transplanting of J. curcas 2-month seedlings proved to be more effective in order to avoid water stress related consequences.