Variation in the dynamic of absorption and efficiency of phosphorus use in tomato.

Changes in root growth and metabolism of P in tomato cultivars are necessary in acidic soils in tropical and subtropical regions in response to P deficiency. This increase in the efficiency of phosphorus absorption by tomatoes can significantly reduce the doses of phosphate fertilizers used, as well as, possibly, the more immediate use of P fixed in the soil matrix, with favorable effects on agricultural sustainability, promoting the use of marginal areas in terms of soil fertility, and the national fertilizer economy. The tested hypothesis was that there would be no difference in the uptake and utilization of P by tomato cultivars; therefore, this study investigated the variation in the dynamics of absorption and efficiency of P-use through changes in the root, stem, leaf, gas exchange, and P-use efficiency in tomato cultivars contrasting P-absorption.

Thermal disruption of the food matrix of biofortified lettuce varieties modifies absorption of carotenoids by Caco-2 cells.

Amongst green leafy vegetables, new varieties of lettuce enriched in lutein and β-carotene are being developed to provide increased supply of dietary carotenoids. We investigated the effect of lettuce genotypes (varieties) and thermal treatments on lutein and β-carotene bioaccessibility to the micellar fraction (and also carotenoid bioavailability) using a human Caco-2 cell model system. Carotenoid absorption by mammalian cells is not correlated with initial carotenoid concentration in fresh lettuce leaves.

New insights into tomato microRNAs.

Cultivated tomato, Solanum lycopersicum, is one of the most common fruits in the global food industry. Together with the wild tomato Solanum pennellii, it is widely used for developing better cultivars. MicroRNAs affect mRNA regulation, inhibiting its translation and/or promoting its degradation.

Trichomes and Allelochemicals in Tomato Genotypes Have Antagonistic Effects Upon Behavior and Biology of .

Tomato genotypes selected for their high foliar zingiberene (ZGB) contents in a segregating F population were assessed to determine their effect on behavior and biology of Koch, the putative resistance mechanisms involved and the role of trichomes on that resistance. Genotypes with contrasting ZGB content (RVTZ-09 = low ZGB, RVTZ-79 = high ZGB, RVTZ-142 = high ZGB, and RVTZ-331 = high ZGB) were selected from an interspecific cross between wild var. accession PI-127826 (high ZGB content and resistant to mites) and cv.

Combining ability of summer-squash lines with different degrees of parthenocarpy and PRSV-W resistance.

The aim was to assess heterosis in a set of 16 summer-squash hybrids, and evaluate the combining capacity of the respective parental lines, which differed as to the degree of parthenocarpy and resistance to PRSV-W (Papaya Ringspot Virus-Watermelon strain). The hybrids were obtained using a partial diallel cross design (4 × 4). The lines of parental group I were 1 = ABX-037G-77-03-05-01-01-bulk, 2 = ABX-037G-77-03-05-03-10-bulk, 3 = ABX-037G-77-03-05-01-04-bulk and 4 = ABX-037G-77-03-05-05-01-bulk, and of group II, 1' = ABX-037G-77-03-05-04-08-bulk, 2' = ABX-037G-77-03-05-02-11-bulk, 3' = Clarice and 4' = Caserta.

Inheritance of parthenocarpy in summer squash (Cucurbita pepo L.).

The inheritance of the tendency to set parthenocarpic fruit in the summer squash (Cucurbita pepo L.) line Whitaker was studied. Two parental lines, Whitaker (parthenocarpic) and Caserta (non-parthenocarpic), and the F1 and F2 generations and backcrosses to both parents were tested.

Yield and post-harvest quality of tomato hybrids heterozygous at the loci alcobaça, old gold-crimson or high pigment.

The effects of the fruit ripening mutant gene alcobaça (alc) and color development mutants, old gold-crimson (ogc) and high pigment (hp), on yield and post-harvest quality of tomato fruits were investigated. Five tomato hybrids were obtained by crossing near isogenic lines with Flora-Dade background [Flora-Dade (alc+/alc+ ogc+/ogc+ hp+/hp+), TOM-559 (alc/alc ogc+/ogc+ hp+/hp+), TOM-591 (alc/alc ogc/ogc hp+/hp+), TOM-593 (alc/alc ogc+/ogc+ hp/hp), and TOM-589 (alc/alc ogc/ogc hp/hp)] with the pollen parent line Mospomorist (alc+/alc+ ogc+/ogc+ hp+/hp+). Hybrid fruit was harvested at the breaker stage and stored on shelves at 15oC and 60% relative humidity for 16 days, and then evaluated for firmness, development of red color, and carotenoid contents.

Inheritance of acylsugar contents in tomatoes derived from an interspecific cross with the wild tomato Lycopersicon pennellii and their effect on spider mite repellence.

Acylsugars present in Lycopersicon pennellii are responsible for the high levels of pest resistance often found in this wild tomato taxon. We investigated the inheritance of acylsugar contents in segregating populations of the interspecific tomato cross L. esculentum x L.

Inheritance of resistance to Meloidogyne incognita race 2 in the hot pepper cultivar Carolina Cayenne (Capsicum annuum L.).

Root-knot nematodes of the genus Meloidogyne are important pathogens affecting vegetable crop production in Brazil and worldwide. The pepper species Capsicum annuum includes both hot and sweet peppers; very little emphasis has been placed on breeding sweet peppers for nematode resistance. We report on the inheritance of resistance to Meloidogyne incognita (Kofoid & White) Chitwood race 2 in the hot pepper cultivar Carolina Cayenne.

Inheritance of resistance to the root-knot nematode Meloidogyne javanica in lettuce.

Resistance to the root-knot nematodes Meloidogyne spp. would be a valuable attribute of lettuce Lactuca sativa L. cultivars grown in tropical regions.