., 2005 ), whereas N is an important factor in determining the growth and nutrient composition of leaf-vegetable sweetpotato. Growth analysis and performance of four sweetpotato cultivars under different levels of N and K (potassium) showed that cultivars
Meng Wei, Aijun Zhang, Hongmin Li, Zhonghou Tang and Xiaoguang Chen
M.C. Palada, S.M.A. Crossman and J.A. Kowalski
Four tropical leaf vegetables commonly used as pot herbs for “kallaloo,” a local West Indian dish, were grown in replicated plots during the fall season of 1996 to determine growth and productivity. Leaf vegetables included green malabar spinach (Basella alba L.), red malabar spinach (Basella rubra L.), sweetpotato (Ipomoea batatas L.), and bush okra or jute mallow (Corchorus olitorius L.). Plants were harvested periodically and data on number of stems or vines, fresh weight of stems and leaves, leaf area, and leaf area index (LAI) were recorded. Except for leaf fresh weight, cultivars or species did not differ significantly in all parameters measured. Leaf fresh weight ranged from 27 g for jute mallow to 198 g for red malabar spinach. LAI was highest for sweetpotato (2.90) and lowest for jute mallow (0.86). Among the species, productivity (fresh weight) was highest (6.78 g/m2 per day) for green malabar spinach and lowest (3.22 g/m2 per day) for jute mallow.
Shigenori Yaguchi, Masanori Atarashi, Masatoshi Iwai, Shin-ichi Masuzaki, Naoki Yamauchi and Masayoshi Shigyo
Eight Allium fistulosum L.–Allium cepa L. Aggregatum group (shallot) monosomic addition lines (2n = 17, FF+1A–FF+8A) have been useful in revealing the effects of single alien chromosomes from A. cepa on the production of l-ascorbic acid in the leaf tissue of A. fistulosum. In this study, the determination of ascorbic acid content revealed that the incorporation of alien chromosome 1A into a diploid background of A. fistulosum increased the internal ascorbic acid content of the leaf blade tissue. We produced a 1A disomic addition in the tetraploid of A. fistulosum (2n = 34) and demonstrated high-frequency transfer of the alien chromosome in crosses with A. fistulosum. Five plants of the 1A disomic additions were regenerated via apical meristem culture of the FF+1A on a Murashige and Skoog medium containing colchicine. These 1A disomic additions showed partial fertility for female and male gametes. Most of the progenies from selfing of the 1A disomic additions and reciprocal crossing with A. fistulosum possessed chromosome 1A. Interestingly, 64% (18 of 28) of the plants obtained from the reciprocal crosses were 1A monosomic additions in a triploid background of A. fistulosum. These monosomic additions were more vigorous and vitamin C-rich than euploid plants of A. fistulosum.
Ambani R. Mudau, Puffy Soundy, Hintsa T. Araya and Fhatuwani N. Mudau
The aim of the current study was to determine the influence of modified atmospheric pressure on the quality of baby spinach during storage. Treatments consisted of control [(normal air) (78% N2; 21% O2)], modified atmosphere (MA) (5% O2; 15% CO2; balance N2), storage temperature (4, 10, and 20 °C), and number of days after storage (0, 3, 6, 9, and 12). Parameters recorded are gas composition, weight loss, sensory quality, minerals and trace elements (Mg, Fe, and Zn), flavonoids, and antioxidant activity. The results of this study demonstrated that in the headspace gas there was overall reduction in O2 and increase in CO2 levels over the storage period. After 6 days of storage, all samples in normal air irrespective of the storage temperature were found to fall short of acceptable marketability with regard to visual appearance. The total antioxidant activity and flavonoids were well maintained under controlled atmosphere (CA) at 4 °C when stored for 9 days.
Fekadu Fufa Dinssa, Peter Hanson, Dolores R. Ledesma, Ruth Minja, Omary Mbwambo, Mansuet Severine Tilya and Tsvetelina Stoilova
Amaranth (Amaranthus sp.) is an important leafy vegetable in Africa where most farmers grow unimproved landraces. Information about amaranth genetic diversity and its adaptation to different environments will help breeders develop improved commercial varieties that meet market requirements. The objectives of this study were to investigate the performances of amaranth entries for vegetable yield across locations and seasons, assess the relative contributions of genetic vs. environmental sources of variation to yield, and cluster locations into mega-environments (MEs) to suggest future test sites. Twenty-six diverse entries were evaluated for vegetable yields in replicated trials at five locations in wet-cool and hot-dry seasons in Tanzania. Season explained the highest proportion (52.1%) of the total sum of squares followed by entries (24.9%) and locations (23.0%). Mean yield across the hot-dry season trials (27.7 t·ha−1) was 47.3% greater than the mean yield across wet-cool season trials (18.8 t·ha−1). Differences among entries in vegetable yield were higher in the hot-dry season than in the wet-cool season, indicating that gain from selection is likely to be greater in the hot-dry season. Most entries performed well in either wet-cool or hot-dry season but a few entries were adapted to both seasons. Two MEs were identified, one characterized by lower altitudes, higher temperatures, and less fertile soils, and a second ME associated with higher altitudes, lower temperatures, and more fertile soils. Each ME may serve as an initial selection site for their respective target environment. Targeting a specific season may give a better chance of finding high-yielding varieties.
Mwanarusi Saidi, Francis M. Itulya, Joseph N. Aguyoh and Mathieu Ngouajio
Kjeldahl method as described by Okalebo et al. (2002) and expressed as mg·kg −1 of plant tissue. Tissue samples analyzed comprised entire above-ground plant parts, including the grain. Cowpea leaf vegetable yield. Leaf vegetable yield data were
, Brassica rapa L. perviridis group. There are many leaf vegetables in this group of B. rapa such as komatsuna and kyona (mizuna and mibuna). Mizuna and mibuna, mizuna and mibuna in Japanese, Brassica rapa L. japonica group. Approximately 300 years ago
Luisa Dalla Costa, Nicola Tomasi, Stefano Gottardi, Francesco Iacuzzo, Giovanni Cortella, Lara Manzocco, Roberto Pinton, Tanja Mimmo and Stefano Cesco
Soil temperature has a crucial impact on physiological processes and growth of plants with important consequences for plant productivity and food safety including nitrate accumulation in leaf blades of leaf vegetables. Consumer demand for high-quality, fresh-cut vegetables has increased rapidly in the last decades, and temperature modulation can help control nitrate concentration in fresh vegetables, an important trait of product safety. Corn salad plants [Valerianella locusta (L.) Laterr., cultivar Gala] were grown at three root temperatures (15, 20, and 25 °C) in a floating system. This experimental setup allowed to directly evaluate the effect of root temperature on yield and plant quality excluding the effect on soil processes and properties. Nutrient solution was renewed weekly and kept aerated while air temperature was maintained constant at 20 °C for all treatments during the entire time of experiments. At harvest, plants were collected, the shelf life evaluated, and the nutrient uptake [NO3 −, iron (Fe) from 59Fe-o,oEDDHA, and 35SO4 2−] and mineral content were determined. Results showed that growing conditions at 20 °C of the nutrient solution led to the best plant performance in terms of yield, nitrate content at leaf level, root biomass, leaf area, and greenness with positive effects on postharvest quality, i.e., less rapid leaf loss of greenness and leaf fresh weight (FW) loss during conservation at 4 °C. At this temperature condition of the nutrient solution, it has also been observed an enhanced functionality of mechanisms involved in the acquisition of nutrients like NO3 −, Fe, and SO4 2−, which are known to play an important role in nitrate level in leaf tissues of crops. Plants grown at 15 °C showed minor growth, whereas the nutrient solution at 25 °C caused stress for the plants affecting negatively the quality and yield. Overall, the results obtained showed that root temperature plays a fundamental role in several plant processes that affect yield and its quality; for hydroponic system cultivations, a level of growing-medium temperature close to that of the surrounding air seems suitable.
Adonai Gimenez Calbo, Marcos David Ferreira and José Dalton Cruz Pessoa
ranging from recently harvested turgidity to visibly wilted leaves. The obtained data for the studied leaf vegetables were compared by use of linear regression analysis. In the pressure probe measurement, especially for chicory, the occurrence of latex
Toshiki Asao, Hiroaki Kitazawa, Kazuyori Ushio, Yukio Sueda, Takuya Ban and M. Habibur Rahman Pramanik
Asao, T. Kitazawa, H. Ban, T. Pramanik, M.H.R. 2004 Search of autotoxic substances in some leaf vegetables J. Jpn. Soc. Hort. Sci. 73 247 249 (in Japanese with English summary). Asao, T