MINERAL CONTENT OF MELON FRUIT (CUCUMIS MELO L.)
Melons are highly demanding, thermophilous plants, which is why they are unpopular among fruit growers. Melon cultivation requires special treatment methods for the improvement of microclimatic conditions. Seven Polish melon cultivars are presently grown on the domestic market. They are well adapted to the local climate. The growth rate, vigor, fruit shape, fruit size, rind color and flesh thickness of those cultivars vary. The objective of this study was to determine the mineral content of edible parts of four field-grown melon cultivars in the Warmia region (NE Poland). This study discusses the mineral content of melon fruit subject to the investigated cultivar and cultivation method. In Poland, melon production is difficult and unreliable. The main problem is the selection of an appropriate cultivar and cultivation method. The analyzed material consisted of four Polish melon cultivars: Malaga F1, Melba, Oliwin, Seledyn F1, grown in a field experiment without protective cover, under polyethylene (PE) sheet cover, under non-woven polypropylene (PP) cover, with soil mulching, as well as with soil mulching under PE sheet cover or nonwoven PP cover. The highest concentrations of total N, K, Ca and Cu were determined in melon fruit of cv. Oliwin. Significant variations in total nitrogen and phosphorus levels in the edible parts of melon plants were noted subject to the applied cultivation method. Cucumis melo L. grown in the control treatment without protective cover was marked by significantly higher levels of total nitrogen and phosphorus in the fruit, compared with fruit grown with the use of other cultivation methods. The results of this study indicate that the fruit of melon plants cv. Seledyn grown in mulched soil under non-woven PP cover was characterized by the most favorable Ca:Mg and Ca:P ratios in comparison with fruit from the remaining treatments.
Impact of PGPR and inorganic fertilization on growth and productivity of sweet ananas melon.
This study was carried out at experimental station in Faculty of Agriculture, Moshtohor, Benha University, Egypt during 2011 and 2012 seasons to improve the morphological and physiological characteristics and yield of sweet ananas melon towards maximizing its growth and productivity using plant growth promoting rhizobacteria (PGPR) in combination with inorganic fertilization and to reduce the using of chemical fertilization for vegetables production. Obtained results could be summarized as the following: the dual treatments of bio and inorganic fertilization gave higher parameters of vegetative growth, photosynthetic pigments content, total fruits yield/ plant and nutritional status compared with the solely fertilization ones. The best results of vegetative growth , photosynthetic pigments content total fruiting/ plant and chemical composition of leaves and fruits were obtained with the application of biofertilizer + full chemical fertilization dose followed by PGPR + 3/4 chemical fertilization without any significant differences. PGPR treatments reduced dose of chemical fertilization and decrease the environmental pollution caused by repeated application of inorganic fertilizers. The role of phytohormones like substances produced PGPR in increasing no. of pistilate flowers/ plant in order to yield was investigated.
Remote estimation of nitrogen and chlorophyll contents in maize at leaf and canopy levels
a b s t r a c t Leaf and canopy nitrogen (N) status relates strongly to leaf and canopy chlorophyll (Chl) content. Remote sensing is a tool that has the potential to assess N content at leaf, plant, field, regional and global scales. In this study, remote sensing techniques were applied to estimate N and Chl contents of irrigated maize (Zea mays L.) fertilized at five N rates. Leaf N and Chl contents were determined using the red-edge chlorophyll index with R2 of 0.74 and 0.94, respectively. Results showed that at the canopy level, Chl and N contents can be accurately retrieved using green and red-edge Chl indices using near infrared (780-800 nm) and either green (540-560 nm) or red-edge (730-750 nm) spectral bands. Spectral bands that were found optimal for Chl and N estimations coincide well with the red-edge band of the MSI sensor onboard the near future Sentinel-2 satellite. The coefficient of determination for the relationships between the red-edge chlorophyll index, simulated in Sentinel-2 bands, and Chl and N content was 0.90 and 0.87, respectively.