Heterosis and combining ability for ornamental chili pepper

Abstract

Ornamental use of Capsicum genus chili peppers has expanded due to easy seed propagation, short germination period, diversified fruit colors and harmony of potted plants. The ornamental plant sector requires cultivars adapted to different cultivation conditions in pots and gardens. Breeding programs can use heterosis and combining ability information, aiming to commercially explore hybrids or develop populations for lineage selection with desirable characteristics. However, the ornamental chili pepper field lacks studies with this data. In this study, combining ability of C. annuum accessions was determined for ornamental purposes and hybrid combinations were identified based on heterosis values. Fifteen hybrids were obtained from diallel crosses of six genotypes of C. annuum, from March to September 2014, under greenhouse conditions, grown in five-liter pots in experimental design of randomized blocks with 10 repetitions and one plant per plot. Morpho-agronomic characterization was conducted based on eight quantitative descriptors: plant height (before and after fruiting); canopy diameter; days to flourishing; days to fruiting; fruit length and diameter, and number of fruits per plant. Both additive and dominance effects play important role in controlling the studied characters, indicating hybrid exploitation as well as development of superior lineages from the progress of segregating generations. Negative heterosis values resulted in reduction in height, time for flourishing and fruiting, as well as fruit diameter and length, which are desirable for ornamental Capsicum breeding program. Considering an ideotype for ornamental chili pepper cultivars, the hybrids UENF 1626 x UENF 1750, UENF 1750 x UENF 2030 and UENF 1626 x UENF 2030 can be recommended for cultivation with ornamental purposes.

Evaluation of the parental and hybrid lines- Heterosis and other genetic parameters among Capsicum annuum genotypes and their hybrids

“…High heterozygosity favours heterosis in many plant species. The F 2 seeds of Tat x Nsky-rw failed in germination; this phenomenon had previously been observed in crosses by some researchers (Silva et al, 2017).…”

Research Article Diallel analysis of quantitative characteristics in ornamental peppers

“…Nascimento et al (2014), working with C. annuum, found that the additive effects were more important for fruit length and diameter and non-additive effects for days for fruiting. Silva et al (2017), also working with C. annuum, verified that the additive effects were more important for plant height before and after fruiting, days for flowering, fruit length, fruit diameter and total number of fruits and non-additive effects for canopy diameter and days for fruiting.…”

“…Regarding canopy diameter, UFSJ 7 and UFSJ 8 expressed positive ĝi values. When used in crosses, these genotypes tend to produce visually more attractive hybrids due to the greater amount of foliage (Silva et al, 2017). UFSJ 7 and UFSJ 8 also expressed positive ĝi values for stem diameter and tend to produce hybrids with higher base of support for the plant.…”

“…Regarding fruit length, diameter and mass, negative ĝi values are preferred in peppers for ornamental purposes since they favor the production of fruits of smaller dimensions but in greater number (Rêgo et al, 2010;Silva et al, 2015;Silva et al, 2017). Negative ĝi values for smaller fruit size were expressed by UFSJ 1, UFSJ 7 and UFSJ 8 parents and negative ĝi values for lower fruit mass were expressed by UFSJ 4, UFSJ 5, UFSJ 6 and UFSJ 8 parents.…”

“…In works with Capsicum sp., several authors such as Ben-Chaim and Param (2000), Doshi and Shukla (2000), Reddy et al (2008), Kamble et al (2009), Rêgo et al (2009), Schuelter et al (2010, Gonçalves et al (2011), Rodrigues et al (2012), Diallel analysis in ornamental peppers 3 Medeiros et al (2014), Nascimento et al (2014) and Silva et al (2017) have used the methodology of diallel analysis to increase information on several quantitative characters of interest. This work carried out the diallel analysis of quantitative characteristics to determine the most promising crosses among eight ornamental pepper parents.…”