A greenhouse experiment was carried out to determine growth, yield, fruit quality, gas exchange and mineral composition of watermelon plants (Citrullus Lanatus L. `Tex'), either ungrafted or grafted onto two commercial rootstocks `Macis' [Lagenaria siceraria (Mol.) Standl.] and `Ercole' (Cucurbita maxima Duchesne × Cucurbita moschata Duchesne) and cultured in NFT. Plants were supplied with a nutrient solution having an electrical conductivity (EC) of 2.0 or 5.2 dS·m–1. The saline nutrient solution had the same basic composition, plus an additional of 29 mm of NaCl. Increased salinity in the nutrient solution decreased total yield. The reduction in total yield in saline treatments compared to control was due to a reduction in the fruit mean mass and not to the number of fruit per plant. Total fruit yield was 81% higher in grafted than in ungrafted plants. The lowest marketable yield recorded on ungrafted plants was associated with a reduction in both fruit mean mass and the number of fruits per plant in comparison to grafted plants. Salinity improved fruit quality in all grafting combinations by increasing dry matter (DM), glucose, fructose, sucrose, and total soluble solid (TSS) content. Nutritional qualities of grafted watermelons such as fruit DM, glucose, fructose, sucrose, and TSS content were similar in comparison to those of ungrafted plant. In all grafting combinations, negative correlations were recorded between Na+ and Cl– in the leaf tissue and net assimilation of CO2 Grafting reduced concentrations of sodium, but not chloride, in leaves. However, the sensitivity to salinity was similar between grafted and ungrafted plants and the higher total yield from grafting plants was mainly due to grafting per se.
Guiseppe Colla, Youssef Roupahel, Mariateresa Cardarelli, and Elvira Rea
Youssef Rouphael, Mariateresa Cardarelli, Giuseppe Colla, and Elvira Rea
on shape index, dry matter, total soluble solids contents, and titratable acidity of mini-watermelon fruits. Concerning the fruit mineral composition, no significant difference among treatments were observed for P (average 1.66 mg·g −1 dry wt
Youssef Rouphael, Mariateresa Cardarelli, Luigi Lucini, Elvira Rea, and Giuseppe Colla
suitability of the different genotypes to be grown in a floating system. The objective of this study was to determine the effect of nutrient solution concentration (4, 20, 36, 52, and 68 mequiv · L −1 ) on biomass production, mineral composition, and the major
Mariateresa Cardarelli, Youssef Rouphael, Delia Muntean, and Giuseppe Colla
effect of increasing levels of nitrate in the nutrient solution on plant growth, quality, SPAD index, chlorophyll fluorescence, leaf pigments, mineral composition, and NUE in five ornamental cabbage cultivars (Coral Prince, Coral Queen, Glamour Red
H. Zekki, L. Gauthier, and A. Gosselin
Tomato plants (Lycopersicon esculentum Mill. cv. Capello) were grown in the three most promising and used hydroponic cultivation systems using rockwool and peatmoss substrates and nutrient film technique (NFT), either with or without recovery and recycling of the drainage solutions. Prolonged recycling of nutrient solutions in NFT caused a reduction in fresh weight, dry weight, and yield compared to plants grown in NFT with regular renewal of the nutrient solution. There were no differences in growth, productivity, and leaf mineral composition between plants grown in rockwool and peatmoss systems, with or without recycling, and in the NFT system without recycling. These results suggest that recycling drainage solutions is an economically and environmentally sound horticultural practice that when used correctly does not cause a reduction in yield of tomatoes cultivated in rockwool or peatmoss. However, prolonged use of the same solution in the NFT cultivation system can negatively affect growth and yield. This is most likely due to an accumulation of sulfate ions in the fertigation solutions.
Harbans L. Bhardwaj and Anwar A. Hamama
in essential nutrients ( Chu and Jeffery, 2001 ; Fahey et al., 1997 ; Murillo and Mehta, 2001 ), no information is available about mineral composition of sprouts made from canola seeds. The term “canola” is a registered trademark of the Canola
Naser Lotfi, Kourosh Vahdati, Bahman Kholdebarin, and Elaheh Najafian Ashrafi
then separately ground to fine powder. Two hundred fifty milligrams of each sample was used to analyze for mineral composition. Statistical analyses. The experimental design was factorial arranged as a completely randomized design with four
Yuhung Lin and Yaling Qian
, S.J. 2004 Growth response of four turfgrass species to salinity Agr. Water Mgt. 66 97 111 Butler, J.D. Hodges, T.K. 1967 Mineral composition of turfgrass HortScience 2 62 63 Carrow, R.N. 2001 Turfgrass soil fertility and chemical problems: Assessment
George Ouma and Frank Matta
Experiments were performed to determine the effect of Accel and carbaryl on the fruit set, yield, quality, and leaf mineral composition of three apples cultivars: `Empire', `Jon-A-Red', and `Braeburn'. The treatments used were Accel at 25, 50, and 75 ppm; carbaryl at 0.05%, 0.1%, and 0.2%. There were significant increases in length: diameter ratio, weight of fruit per tree, pH, and percent red color. Mean fruit weight, percent N, K, and Mg as the rates of Accel and carbaryl increased. Sugar content in the fruit and the levels of P, Ca, Mn, Fe, Cu, and Zn in the leaves were not affected. We conclude that the increased fruit weights were due to increased cell numbers and the few fruit that remained after thinning, thereby leading to increased amounts of assimilates directed to the developing fruit. The increase in percent red color is indicative of the effect of the treatments on the degree of ripening.
B. Marangoni, D. Scudellari, and M. Toselli
Mature trees of Stark Redgold nectarines grown in silt loam soil in the Po Valley were tested at five fertilization regimes and compared to untreated control: N1 (100 kg N/ha), N1 (100 kg N/ha, split 60% in spring and 40%. in postharvest), N2 (200 kg N/ha), N1 (100 kg N/ha) + K (150 kg K2 0/ha), N2 (200 kg N/ha) + K (150 kg K2 O/ha). The annual distribution in spring was equally split before full bloom and at fruit set.
The data collected over the three trial years show no differences as compared to control in yield and fruit size. N2 delayed ripening and decreased fruit quality. Leaf mineral composition was affected by potassium; maximun N induced leaf accumulation of N-NH4 The high concentration of K in leaf tissues was correlated to the yellow color of the leaf blade. Total leaf chlorophyll content was measured by an Spad-502 chlorophyll meter (Minolta Corp.) and compared to that measured by conventional technique (Arnon method). The overall findings suggest the amount of N used in peach fertilization can be reduced.