No abstract

Family farmers in the western Santa Catarina state, Brazil, have conserved local dryland rice varieties. However, the literature lacks data about the milling performance of these varieties, as well as about the effects of genotypes, environment and genotype x environment interaction. The current study aimed to evaluate the milling yield, as well as whole, broken, white-belly and chalky grains, in experiments designed in complete randomized blocks, with four replications, in two sites. The rates for milling yield and whole and broken grains were, respectively, 57.93-69.90 %, 38.73-66.0 % and 3.40-22.15 %, with 15 local varieties reaching values similar to those recorded for modern dryland rice varieties. The Anchieta county (origin of the varieties) recorded the highest values for milling yield and whole grain. The incidence rates for white-belly and chalky grains were, respectively, 0.10-8.68 % and 0.02-3.12 %. Significant differences (p ≤ 0.05) were observed for genotype, environment and genotype x environment interaction effects, concerning the milling yield. For whole and broken grains, the differences were significant (p ≤ 0.05) for genotype and environment, but not significant for genotype x environment interaction. For white-belly and chalky grains, the differences were significant (p ≤ 0.05) for genotype and genotype x environment interaction, but not significant for environment. For all the studied milling yield variables, differences were observed for the varieties' stability, as well as established a stability ranking.

The far west region of Santa Catarina (FWSC) state in southern Brazil was indicated as a microcenter of diversity of the Zea genus. In this region, local popcorn varieties are grown in small areas, but in a significant number of farms. The present study aimed to characterize the diversity of 41 local populations from that region, based on phenology and morphological characters of plant, ear and grain. Therefore, an experimental design of complete randomized blocks with two replications was conducted. The data allowed to identify a rich diversity of popcorn in the FWSC for the characteristics of plant, ear, and grain, as well as for the phenology. For the color, 20 populations presented white grain, nine black, nine yellow, two red and one orange. Regarding the cycle, all varieties of yellow and round grains were considered hyper early/early and the varieties of white grains, intermediate/late. Average plant height varied from 1.8 to 3.2 m, while the weight of one thousand kernels varied from 80.9 to 200.4 g. The accumulated day degrees for tasseling ranged from 689.05 to 1,090.57. Based on the cluster analysis of qualitative and quantitative characters, three groups were formed, and five populations were isolated. The inclusion of plant characteristics and phenology can be an important and complementary tool for studies in popcorn races. Trends in some plant characteristics were observed within popcorn varieties with the same grain features. This result is important information for popcorn genetic breeding strategies.

Drought is the main factor of abiotic stress in dryland rice cultivation, responsible for considerable productivity losses and grain quality damages, as well as genetic erosion of local varieties of this crop. The use of indices in the drought tolerance estimation in grains of this crop is acquiring importance for its advantages in the operationalization of tests of comparison between genotypes and their effectiveness in the differentiation of responses to drought stress. Among local dryland varieties of rice preserved by small-scale farmers in far western Santa Catarina, different responses to drought tolerance are expected. The identification of these differential responses is important in the context of agrobiodiversity conservation, genetic improvement, and as an alternative to the effects of climate changes. The objective of the present study was to evaluate thirty-four local varieties of dryland rice from far western Santa Catarina regarding drought tolerance. For this aim, this work used the DTD (Drought Tolerance Degree) methodology. Fifteen varieties showed greater resistance when submitted to a water restriction level of 10% in water moisture. On the other hand, six varieties were more resistant to moderate stress (20%). Finally, three varieties were among the most resistant in the two applied stress levels.

Sweet corn (Zea mays L.) local varieties are important gene sources for breeding programs, mainly in participatory research models. This study aimed to evaluate the agronomic performance of seven sweet corn local varieties (2255A, 2029A, 2276A, 2514A, 3000A, 741B and 319A) carrying the sugary1 gene under homozygotic condition and two controls, at four environments [Anchieta (altitudes: 422 and 717 m), Guaraciaba (altitude: 624 m) and Florianópolis (altitude: 5 m)], in the Santa Catarina state, Brazil. The varieties 3000A and 319A showed a good performance in the different altitudes for ear and grain length and ear yield. At intermediate altitudes (422 and 624 m), the mean husked ear yield (milky grain) of these varieties were close to 12.5 t ha-1 (3000A) and 10.0 t ha-1 (319A). The varieties 2029A, 741B, 2514A, 2276A and 2255A stood out for ear length and diameter, number of ear rows and grain length. The best performance of the sweet corn local varieties was observed in their region of origin, mainly at altitudes ranging from 400 to 650 m. These varieties are adapted to the region and are promising alternatives to be used in breeding programs focused on finding a greater potential variability for selection purposes.