Thermal requirement of indian mustard (Brassica juncea) at different phonological stages under late sown condition

Abstract

Indian mustard [Brassica juncea (L.) Czern & Coss.] is a long day plant, which requires fairly cool climatic condition during growth and development for obtaining better seed yield. Various workers have correlated crop growth and development with energy requirement parameters, such as growing degree days (GDD), photo-thermal unit (PTU), helios thermal unit (HTU), photo-thermal index (PTI) and heat use efficiency (HUE). Therefore, GDD requirement for different phenological stages of 22 newly developed Indian mustard varieties was studies during winter (rabi) seasons of 2009–10 and 2010–11 at student instructional farm of C.S. Azad University of Agriculture and Technology, Kanpur, (Utter Pradesh). Study revealed that RH-8814, NRCDR-02 and BPR-549-9 recorded higher GDD (1703.0, 1662.9 and 1648.0), PTU (19129.8, 18694.2 and 18379.8), HTU (11397.7, 11072.2 and 10876.0), PTI (13.25, 13.14 and 13.08) and HUE (4.11, 3.84 and 3.71) at physiological maturity, while higher HUE was recorded (9.62, 8.99 and 8.91 kg ha−1 degrees-day) at days after sowing (DAS) to 50 % flowering. On the basis of study mustard genotypes RH-8814, NRCDR-02 and BPR-549-9 were identified as most heat-tolerant, as they maintained higher values for energy related parameters. Seed yield was highly positively correlated with GDD (r = 0.61, 0.65 and 0.75), PTU (r = 0.66, 0.64 and 0.74), HTU(r = 0.79, 0.68 and 0.73) at the above these three phenological stages, while negatively correlated with PTI at anthesis and at maturity. Hence, these parents could be used in crossing programme for achieving further improvement.

Effect of sowing dates and nitrogen levels on total dry matter and its partitioning at different growth stages and yield of Indian mustard (Brassica juncea L.)

“…This decline in response of nitrogen at higher doses may be explained with the well established Mitscharlich equation. Table 3: Effect of sowing date and nitrogen levels on yield attributes, yield and oil content of Indian mustard (pooled over 2 years) Singh et al, (2014) and Keivanrad et al, (2012) were also reported similar findings.…”

Impact of Sowing Date Induced Temperature and Management Practices on Development Events and Yield of Mustard

“…Daily temperatures were recorded for computing required growing degree days (GDD) for different stages. GDD were computed by using daily normal maximum air temperature, minimum air temperature, mean air temperature and considering base temperature of 5º C for mustard (Singh et al, 2014). The sum of degree days for the completion of different development stage of mustard were obtained by using the following formula (Kumar et al, 2008); Accumulated GDD (º C day) = Summation (Daily mean air temperature in º C -Base temperature of mustard).…”

Photosynthetic performance responses in different phyiological development stages of some Brassica juncea genotypes in field condition

“…The crude oil content was determined by grinding 10 g of powdered mustard seed samples and extracting by hexane that were used with Gerhardt 2000 soxhlet apparatus (Singh et al, 2014 Mesophyll conductance was calculated by dividing Pn by…”