Evaluation Of Seed Filling Problems In Some Hybrids And Openpollinated Sun Flower (Helianthus Annuus L) Cultivars, As Affected By Pollination And Sowing Dates

Abstract

A field experiment was conducted at the College of Agricultural Studies,

Sudan University of Science and Technology, Sudan, Khartoum, during

summer 2014 and 2015, to study the effects of sowing date, pollinations and

cultivars on seed setting and seed filling of sunflower (Helianthus annuus

L).The cultivars were Hysun33 and local .The experiment was factorial

experiment with three factors in a randomized complete block design (RCBD)

with four replications. Two cultivars, local (PAN-7351 LC) and hybrid

(Hysun-33) were used. Plants were grown in three different sowing dates

(March, May, JulyS1 S2 S3)and two type of pollination(open pollination and

cover pollination). Growth parameters studied were Plant height, leaf area, number of seeds setting/head, number of seeds filling/head, hundred seed weight , hundred

seeds filling weight, head diameter, dry weight, seeds setting (%),seeds filling

%and The efficiency. The results showed that sowing dates were highly

significant for most of the parameters in both seasons ( leaf area, number of

seeds filling per head, head diameter, dry weight).The sowing date revealed

highly significant effect in season one, namely in number of seeds setting per

head, seeds setting percentage and the efficiency. Significant differences

between the two types of pollination were revealed in some characters in first

season namely plant height, number of seeds setting per head, , number of

seeds filled per head, seeds filling percentage, Seeds setting percentage and

the efficiency and highly significant differences on weight of hundred seeds

setting. Moreover, analysis of variance indicated highly significant effects of

pollination on most characters, number of seeds setting per head, number of

seeds filling per head, weight of hundred seeds filling, head diameter, dry

weight, seeds setting percentage, seeds filling percentage and the efficiency

in second season. Also there were significant differences among sunflower cultivars in plant height which was highly significant in season two. The analysis of variance indicated highly significant differences among sunflower cultivars in most yield and yield components, namely number of seeds setting per head, , number of seeds filling per head, weight of hundred seeds filled, seeds setting percentage.