N. Njoroge, B. Gemmill, R. Bussmann, L.E. Newton and V.W. Ngumi
Jomo Kenyatta University of Agriculture and Technology, Botany Department, P.O. Box 62000 Nairobi, Kenya. Food and Agriculture Organization of the United Nations, Viale delle Terme di Caracalla, 00100 Rome, Italy. Economic Botany, Missouri Botanical Gar
Abstract: Citrullus lanatus (Thunb.) Mansf. (Watermelon) is an important crop plant in Kenya. Being monoecious, watermelon is entirely dependent upon pollination services usually by insects for production. Although the centre of origin for this plant is thought to be tropical Africa, essentially not much has been studied of its pollination requirements in this region. The current study investigated the identity of the wild pollinators of watermelon, their behaviour and relative pollination efficiencies at Yatta, a farm near Thika (Eastern Province). The main pollinator for this crop was found to be the honey bee, Apis mellifera but three wild species of Lasioglossum were found as important pollinators. These wild bees have a significantly higher (P< 0.0001) pollen deposition on stigmas of watermelon than honeybees. One of the Lasioglossum (Ctenonomia)sp. 4 deposited on average three times as much pollen as the honeybee. At about the time of stigmatic receptivity, the number of visits by this species to female flowers increases until it equals visits to male flowers irrespective of number of flowers per plot. This behavioural pattern coupled with the high pollen deposition potential makes Lasioglossum (Ctenonomia)sp. 4 a superior candidate as an alternatively managed pollinator for watermelon. Knowing that visitation occurs mostly in the morning, and that flowers last only for one day, spraying can be done in the later hours of the day when the pollinators have virtually stopped foraging on the flowers. In view of the reported pollinator decline globally, the wild pollinator species reported in this study warrant further investigation on their nesting biology and potential for domestication.
Bhusan Gurung and K.K. Singh
G.B. Pant Institute of Himalayan Environment and Development, Sikkim Unit, Pangthang, Post Box 24, Gangtok, East Sikkim-737101, India.
Abstract: The first successful micropropagation protocol was developed for an important Sikkim Himalayan Rhododendron, R. dalhousiae Hook. f. also known as Lahare Chimal in Sikkim. In vitro raised shoot tip explants from R. dalhousiae were used to produce multiple shoots on a medium containing various concentrations of growth regulators. Among the combinations used, Murashige and Skoog (MS) medium containing 5 mg L-1 2-isopentenyladenine (2iP) along with additives such as, 100 mg L-1 polyvinyl pyrrolidone (PVP), 100 mg L-1 ascorbic acid, 10 mg L-1 citric acid was found to be best for induction of multiple shoots within 12 weeks of culture. The combination of 5 mg L-1 2iP +1 mg L-1 indole-3-acetic acid (IAA) resulted in further multiple shoot production than using them alone. Rooting of shoots in vitro was achieved on MS medium containing 0.2 mg L-1 indolebutyric acid (IBA). Rooted plantlets were transferred to small polythene bags containing autoclaved fresh peat moss and soil (1:3) and maintained with a high humidity for acclimation. These in vitro-raised plants grew normally in greenhouse and natural habitat (arboretum of the Institute) without showing any morphological variation. The protocol developed from the present study could be used for large scale multiplication of R. dalhousiae in a limited time.
M. Bejoy, M. Dan, N.P. Anish, Githa Ann George and B.J. Radhika
Plant Genetic Resource Division, Tropical Botanic Garden and Research Institute, Palode, Trivandrum 695 562, Kerala, India.
Abstract: An efficient and repeatable micropropagation protocol has been established for Amomum hypoleucum, a lesser known threatened medicinal plant of the family Zingiberaceae. Eighty percent of the rhizome nodes from greenhouse grown plants, cultured on MS medium supplemented with 1 mg L-1 BA and 0.5 mg L-1 IAA, showed axillary bud break in 8-10 days. Multiple shoots proliferated from such shoot explants when transplanted to medium with 3 mg L-1 BA and 1 mg L-1 TDZ. An average of 9.2 shoots could be recovered in two months and about 65-70% of the shoots showed simultaneous rooting. Isolated shoots were also rooted in medium fortified with 0.5 mg L-1 NAA. Plantlets, transferred to the field after acclimatization in greenhouse conditions, showed 85% survival.
Agricultural Research Institute, Ministry of Agriculture, Natural Resources and Environment, P. O.Box 22016, 1516Nicosia, Cyprus.
Abstract: Lettuce plants (Lactuca sativa L. cv. 'Paris Island') were grown in an unheated plastic greenhouse to determine the effects of solution nitrogen concentration and growth regulators (gibberellin and kinetin) on growth (fresh and dry head weight) and tissue nitrate content (TNC). The plants were grown in plastic containers with perlite and supplied with a basic nutrient solution supplemented with nitrogen (N) corresponding to 50, 100, 150, and 200 ppm NO3-N. Growth regulators; gibberellin (GA3) and kinetin were applied at different doses independently and in combination. Fresh, dry weight and TNC were responsive to N application level. However, fresh and dry weights were similar at 150 and 200 ppm and TNC at 100 and 150 ppm nitrogen supply. Gibberellin (GA3) and gibberellin and kinetin in combination (GA3+kinetin) enhanced fresh and dry weight and TNC compared to the control. There were few differences in response to application rates. Therefore, where lettuce plants are grown in similar conditions and low NO3 accumulation is desirable, together with high yield and good size, the best N application level is 150 ppm NO3-N and growth regulators application may enhance yield. However their use in reducing the nitrate content is not recommended.
S. Protain, M. Mohammed and L.A. Wilson
The University of the West Indies, Department of Food Production, Faculty of Science and Agriculture, St. Augustine, Trinidad, West Indies.
Abstract: The process of ripening was evaluated in three papaya cultivars, Solo Sunrise (SS), Tainung #2 (T2) and Red Lady (RL) with different mean fruit weights of 387, 1364 and 2266 g and fruit cavity void volumes of 56, 334 and 502 mL and fruit weight/cavity void volume ratios of 6.9, 3.8 and 4.3 g mL-1, respectively. The evaluation was done by comparing physiological determinants of the ripening process; ethylene (C2H4) generation and respiratory CO2 production, measured at two temperature ranges, 20-22oC and 28-30oC, by sampling cavity void volumes, with physico-chemical quality characteristics of ripening: skin colour, flesh firmness and pH. Fruit ripening of the three cultivars was delayed at the lower temperature range as measured both by physiological determinants including pre-and peak climacteric rates and physico-chemical quality characteristics. However, cv RL showed slower ripening than cvs SS and T2 at both temperature ranges, probably partly related to its low fruit weight/cavity void volume of 4.3 g mL-1. Moreover, there were negative temporal displacements for skin degreening compared with those for flesh softening, respiration and ethylene generation in fruit of the three cultivars. Fruits of cvs SS and T2 were fully ripened in 8 days after harvest (DAH) and RL fruits in 10 DAH at the lower temperature range. Values for C2H4 generation and CO2 production measured in the fruit cavity are judged to be sensitive indicators of the progress in the process of ripening.
S. Akbari Chermahini, N. Moallemi, A. Shafei Zargar
Department of Horticulture, Chamran University, Ahvaz, Iran, Safiabad- Dezful Agricultural Research Center, Dezful, Iran.
Key words: Nitrogen, flowering, fruit set, 'Valencia' Orange
Abstract: Yield of fruit tree is determined primarily by flowering intensity and subsequent fruit set. Flower number and fruit set are also influenced by endogenous nitrogen level. This research was concerned with the effect of winter foliar application of urea on flowering and fruit-set of 30-year-old 'Valencia' orange on sour orange rootstock at Safiabad Agricultural Research Center of Dezful. Treatments included urea foliar application at 3 levels (0, 0.5, 1%) and 2 times of application (6 and 9 weeks before full bloom). The experimental design was a factorial randomize complete block with 4 replications. Nitrogen percentage in leaf, flower number, ovary diameter and fruit set were studied. Results showed that winter application of urea increased the level of N for 2 weeks. Different levels of urea increased the number of flowers, ovary diameter and fruit set. The higher concentration of urea (1%) had more effect. Considering the time of application, urea spray 9 weeks before full bloom had the highest effect on flowering but urea spray 6 weeks before full bloom resulted in higher ovary diameter and fruit set.
S. Ramakrishnan, R. Umamaheswari, T Senthilkumar and M. Samuthiravalli
Department of Nematology, Centre for Plant Protection Studies, Tamil Nadu Agricultural University, Coimbatore - 641
Abstract: Experiments were conducted for the management of root knot nematode, Meloidogyne incognita using non-chemicals under controlled and field conditions in medicinal crops viz., ashwagandha (Withania somnifera)and senna (Cassia angustifolia). All the treatments comprising of bioagents, organic amendments and humic acid were effective to suppress M. incognita population and to increase the plant biomass and yield of economic parts of these crops. Among the treatments, the use of plant growth promoting rhizobcaterium, Pseudomonas fluorescens available commercially in talc formulation (2.6 X 106 cfu g-1) at 2.5 kg ha1 as soil application recorded the lowest nematode population accompanied with highest economic yield.
P. Aggarwal, A.K. Bakshi and J.S. Kanwar
Department of Food Science and Technology & Department of Horticulture, Punjab Agricultural University, Ludhiana-141004.
Abstract: Two cling stone peach cultivars "Shan-i-Punjab" and "Tropic Beauty" and one free stone cultivar "Florda Grande" were processed for canning (whole and halves) and beverages (squash and nectar). Fruits of Shan-i-Punjab were found to have the best characteristics for canning (as whole) and for making pulp based beverages (nectar and squash) with maximum ascorbic acid content (17 mg/100 g) and pulp yield (47.62%). Organoleptically Shan-i-Punjab fruits were found to have the highest acceptability scores i.e. 8.50 for canned peaches, 8.58 for squash and 8.38 for nectar among all the cultivars studied on a 9-point Hedonic scale judged by eight semi-trained panelists and general consumers. Florda Grande also received the higher acceptability scores (8.50) for its canned peach halves because of its tough texture. The fruits of Florda Grande were not much suitable for pulp based beverages, whereas those of Tropic Beauty were found acceptable for canning as well as for making beverages at zero time and also after six months storage.
Shamsa Fazel, Monsef Hamidreza, Ghamooshi Rouhollah and Mohammadreza Verdianrizi
Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran. Department of Pharmacognosy, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.
Key words: BCG, total alkaloids, medicinal plants, determination
Abstract: A simple spectrophotometric method based on the reaction with Bromocresol Green (BCG) was developed for determination of total alkaloids in medicinal plants. A yellow complex forms and is easily extractable by chloroform at pH 4.7. The absorbance of the complex obeys Bear 's law over the concentration range of 4-13 ug atropine per mL of chloroform. This procedure can be carried out in the presence of other compounds without interference.
R.K. Sharma and K. Prasad
S.C.I. India Ltd., Bhagalpur - 812001, Bihar. Department of Food Engineering and Technology, SLIET, Longowal - 148 106, Punjab.
Key words: Okra, Abelmoschus esculentus, correlation, variance, principal component.
Abstract: Twenty selected genetically diverse okra strains were evaluated using Principal Component and cluster analysis for the extent of variability and relationship between various economically important traits for the purpose of genetic improvement. The trial was laid out in a randomized block design (RBD). Positive significant correlation for days to 50% flowering (DF) with days to first harvest (DFH), number of pod per plant (NP) with pod yield per plant (PY) and pod yield per plot (PYP) (P<0.001) and PY with PYP (P<0.001) and negative correlation was observed for pod weight (PW) with NP (P<0.01). The analysis of extracted components, component pattern and Eigen values revealed that the first two principal components alone accounted for 53.25% of variance. First component was found heavily loaded with days to 50% flowering (DF), days to first harvest (DFH), pod length (PL), pod diameter (PD) and pod weight (PW), which comprised of fourteen genotypes in three clusters. The matrix obtained from principal component analysis revealed that the genotype Pb- 57 and HRB-9-2 found their positions in same cluster in principal space. Dominating similar prominent phenotypic characters formed separate place in principal space as coherent cluster. Cluster based inter breeding of genotypes would exhibit high hetrosis and is also likely to produce new recombinants with desired characters in okra.
M.A. Hegazi and G.A.N. ElKot
Department of Horticulture (Floriculture), Department ofAgriculture Botany (Phytopathology), Faculty ofAgriculture, Kafr El-Sheikh University, Kafr el-Sheikh, Egypt.
Abstract: A field experiment was carried out during two successive seasons at the Experimental Farm of the Faculty of Agriculture, Kafr El- Sheikh University to evaluate some essential oils as biocontrol agents for powdery mildew on Zinnia elegans, L. Marjoram, clove, cinnamon, garlic, ginger and fennel oil were used as a foliar spray at 2 levels (250 and 500 ppm) beside Kema zein 75% and distilled water as a control. The plants were sprayed four times beginning from June 15th with one week interval by a hand atomizer as soon as the first sign of powdery mildew detected on plants. Disease incidence and severity as well as vegetative parameters such as plant height, number of branches per plant, leaf area, fresh and dry weights of shoots, root length and fresh and dry weights of roots were determined in the two seasons. Peroxidase and polyphenol oxidase activities were determined after 24 hour from the last spray in leaves samples. The highest significant decrease in disease incidence and severity and the best results for most of the studied growth and flowering parameters and total green colour were recorded when plants were sprayed with ginger, cinnamon and clove oils, respectively each at 500 ppm compared to the other treatments in both seasons. In addition, the activities of peroxidase (POX) and polyphenol oxidase (PPO) enzymes increased as a result of oil spray on plants. In conclusion, these findings provide a rational basis for possible utilization of these essential oils as a safe and alternative method to fungicides for controlling powdery mildew in zinnia plants.
Sait Engindeniz, Murat Yercan and Hakan Adanacioglu
Ege University, Faculty of Agriculture, Department of Agricultural Economics, Bornova-Izmir/Turkey.
Key words: Capitalization rate, orchards, income capitalization approach, olive, valuation.
Abstract: Valuation of orchards is an important issue in condemnation, taxation, loan, insurance, inheritance, and purchase-sale cases. The approach to be used for orchards may vary according to the purpose of appraisal, age of the establishment, obtainable data, and according to the current regulations. In this study, land and tree values of olive orchards in a selected region from Turkey were determined by the periodic income capitalization approach. For this aim, four villages were selected and data was collected from 55 farmers selected randomly. While determining the value of the olive orchards with trees, past values approach was used. The capitalization rate for the income capitalization approach was determined as 5.32%. The value of bare land of olive orchards over periodic net income was calculated to be $ 19,684.87/ha. Tree values per hectare varied between $ 9,189.86 and $ 16,768.13 according to tree ages.
Samson Bekele Diro and Ketema Tilahun
Amhara Regional Agricultural Research Institute, Sekota, Ethiopia. Amhara Regional Agricultural Research Institute, Sekota, Ethiopia. Presemt address: School of Agricultural and Wine Sciences, Charles Sturt University, Locked Bag 588, Wagga Wagga NSW2678,
Abstract: Deficit irrigation conserves water and minimizes adverse effects of excess irrigation. In this study, the applicability of the CROPWAT model in management of deficit irrigation was evaluated at Sekota Agricultural Research Center, Ethiopia. Water was applied using low head drippers. There were eight treatments with three replications: stress at 1st, 2nd, 3rd, and 4th growth stages and partial stresses of 50% ETc, 75% ETc with two controls of 25% ETc and 100% ETc of the water requirement throughout the growing season. The input data for CROPWAT program were climatic, rainfall, crop and soil data. Yield reductions simulated by CROPWAT program were comparable with yield reduction measured under field condition. Model efficiency and correlation coefficients of 98% were obtained. Based on the above comparative analysis, CROPWAT program could adequately simulate yield reduction resulting from water stress.
Mahmoud M Hamdi, Naima Boughalleb, Neji Tarchoun and Lassaad Belbahri
1Department of Agronomic and Economic Sciences, Higher School of Agriculture of Kef, 7119, Kef Tunisia, 2Department of Biological Sciences and Plant Protection, Higher Institute of Agronomy of Chott Mariem, 4042, Sousse, Tu
Key words: Tomato, Lycospersicon esculentum, graft, Fusarium crown and root rot, grafting, Beaufort x Bochra, Beaufort x Amal, Kemerit x Bochra and Kemerit x Amal, rootstock
Abstract: Tomato, Lycospersicon esculentum, is an important vegetable crop in Tunisia and many other Mediterranean countries. Fusarium crown and root rot of tomato are new diseases in the area, first reported during 2000-2001 crop season, threatening tomato production. Being a soil-borne pathogen, effective disease control methods of Fusarium crown and root rot are limited thus requiring the alternative measures for disease management. In this study the efficacy of grafting commercial Tomato cultivars Bochra and Amal, used as scions, onto a new rootstock Beaufort and Kemerit RZ was examined in controlled and natural conditions. Grafting was found, in this study, to be an effective method to attenuate the impact of Fusarium wilt, Fusarium crown and root rot. Moreover, grafting increased tomato growth parameters, yield and improved fruit quality.
Jianming Li, Xiaoyan Wang, Zhirong Zou and M.H. Behboudian
College of Horticulture, Northwest A&F University. Yangling, Shaanxi Province 712100 China, Department of For?eign Languages, Northwest A&F University. Yangling, Shaanxi Province 712100 China, Institute of Natural Resources, Massey University, Palmerston
Key words: Upper-limit, soil water content, yield, fruit quality, tomato, cucumber
Abstract: This study was conducted to determine the optimum upper limit of soil water content (SWC) for tomato and cucumber from early stages after transplanting. Five different upper limits of SWC were tested at the lowest limit of 60% of field capacity (FC) for tomato and of 75% for cucumber. Stem growth, root viability, yield and fruit concentrations of vitamin C and total soluble solids were significantly affected by the treatment. The highest yield and best fruit quality was obtained at 85% of FC for tomato and at 90% for cucumber. This suggests that irrigating to FC does not necessarily result in higher yields and better fruit quality.