Features of determining the technological indicators of grain in hybrids of popcorn (Zea mays L. everta Sturt.)

Abstract

Purpose. The purpose of the research was to study the influence of the duration of the period from harvesting to popping on the technological indicators of popcorn grain.Methods. The experiment was conducted in the labora- tory of breeding corn of mid-ripening and mid-late hybrids of SE Institute of Grain Crops of the National Academy of Agrarian Sciences of Ukraine. The material for the research was 14 experimental trilinear popcorn hybrids of our own selection. Technological indicators of grain were studied according to the method developed at the SE Institute of Grain Crops of the NAAS in 2023. The Clatronic PM 3635 was used for popping at 5, 25, 45, 60, 75 and 90 days after harvest. The popping expansion, percentage of unpopped kernels and number of popcorn flakes were determined separately for each hybrid for each type of popping.Results. Popping expansion (PE) varied from 25.5 cm3/g to 47.5 cm3/g, and the mean values o f the trait varied from 34.0 cm3/g on day 5 after harvest to 39.6 cm3/g on day 60. In 50% of the hybrids, the highest PE was observed on the 60th day after harvesting. In general, 93% of popcorn hybrids showed an increase in PE from day 5 to day 60, and after day 60 it remained unchanged in 29% of hybrids, increased in 42% of hybrids, and decreased in 29% of hybrids. The percentage of unpopped kernels in popcorn hybrids varied from 0% to 10.6%, and the average values of this indicator varied from 2.51% to 3.14%. In 60% of the hybrids, the percentage of unpopped kernels did not exceed 5% throughout the study period, which corresponds to the assessment of “excellent”. The length of the period from harvest to popping also affected the type of popcorn.On day 5, none of the hybrids had a “predominant type of popcorn,” i.e., a type that had ≥ 75% in 2 replicates. At 90 days after harvest, 6 hybrids had “predominant type of popcorn.” Analyzing the composition of popcorn at 5, 60, and 90 days after harvest, it was found that the average percent- age of “bilateral popcorn flakes” was 20%, 63%, and 69%; “multilateral popcorn flakes” – 30%, 14%, 11%; “unilateral popcorn flakes” – 27%, 18%, 18%, and “mushroom-shaped popcorn” – 24%, 5%, 3%, respectively. The time of popping had a strong positive relationship with the popping expan- sion and the bilateral popcorn flakes and a strong negative relationship with the multilateral popcorn flakes, unilateral popcorn flakes and mushroom-shaped popcorn types.Conclusions. It was established that the duration of the period from popcorn harvesting to popping affects the tech- nological indicators of grain. With increasing time, the pop- ping expansion increases and the percentage of unpopped kernels decreases. It has been proven that popping should be carried out no earlier than 60 days after harvesting. It was found that with the increase in the popping expansion, the percentage of bilateral popcorn flakes increases, while the percentage of other popcorn flakes decreases. It was shown that on the 90th day only 48% of hybrids formed the predominant type of popcorn. It was established that, according to the results of the study of technological indi- cators, the following hybrids are suitable for commercial use 90 days after harvesting: (Cyclone × RS 19) – popping expansion – 47.0 cm3/g; popping – 100%; type of popcorn – "bilateral popcorn flakes" and (Cyclone × RK 25) – popping expansion – 47.5 cm3/g; popping – 100%; type of popcorn – "bilateral popcorn flakes".