Seeds of Tomato (Solanum lycopersicum L.) Hybrids Incorporating rin, nor, or alc Alleles Exhibit Heterosis for Yield and Quality Traits

Abstract

The high price of hybrid seed of tomato (Solanum lycopersicum L.) may be compensated for by realized higher profits obtained from cultivation of hybrids. The objective of the present study was to ascertain the magnitude and direction of relative heterosis in hybrids involving rin, nor, or alc alleles for yield and quality traits, as well as the existence of correlation among relative heterosis for these traits. Significant relative heterosis was observed for all the traits. Not even a single hybrid exhibited significant and negative relative heterosis for marketable yield and number of fruits per plant. The magnitude of relative heterosis varied from −37.06% to 45.72% for average fruit weight, −13.68% to 11.36% for pH, and −53.73% to 54.62% for ascorbic acid. The F₁ hybrids of tomato had, in general, higher marketable yield and number of fruits per plant as compared with their mid-parental values. However, the average weight, pH, and ascorbic acid of fruits of tomato hybrids were higher, lower, or equal to their mid-parental values. The increase in yield of most of the hybrids was accompanied by an increase in fruit number, fruit weight and ascorbic acid but was not correlated with increase or decrease in pH. Fruit number played greater role than fruit weight in improving marketable yield of tomato hybrids. Future studies on tomato may be aimed to validate the existence of a correlation among an increase in ascorbic acid of hybrids with a simultaneous increase in their marketable yield, fruit number and fruit weight.

Keywords:

• ascorbic acid
• alc
• fruit number
• fruit weight
• hybrid
• nor
• rin
• tomato
• yield