H.S. Grewal’s research while affiliated with Punjab Agricultural University and other places

The experiment was conducted to evaluate the effect of growing media compositions containing cocopeat, FYM and vermiculite in different ratios on potted Chrysanthemum morifolium Ramat cultivar Kikiobiory (standard) for quality flower production. The results revealed that, vegetative growth with maximum plant height, number of leaves, root suckers per plant with delayed flowering were observed in media containing cocopeat + FYM (2:1)., whereas, the flower quality parameters like flower diameter and duration of flowering were highest in media containing vermiculite + FYM (2:1). However, plants showed the significant vegetative growth with better flowering time and quality in media composition cocopeat + vermiculite + FYM (1:1:1). Therefore, the findings suggest that for quality flower production of potted Chrysanthemum cv. Kikiobiory, light-weight growing media composition of cocopeat + vermiculite + FYM (1:1:1) was ideal with better plant morphological development and sustained flowering for display.

The photoperiodic night interruption to schedule efficient flowering time in Chrysanthemum morifolium Ramat cv. Anmol according to demand of its flowers in the market was monitored. The influence of six night interruption treatments i.e. control, <5 second flash, 30, 60, 90 and 120 min were studied on the morphological development of Chrysanthemum morifolium Ramat cv. Anmol. The results revealed that the plant height, number of branches, leaves and root suckers per plant were positively affected with increased duration of night interruption. The flowering time was significantly delayed from mid December to end of February (two months) and number of flowers per plant increased as the duration of night interruption was increased from control to 120 min. Therefore, the night interruption durations studies were helpful to schedule the sustainable flowering time in Chrysanthemum cultivar Anmol by around two months with better plant growth.

The light-weight growing medium compositions were evaluated in the present study for optimum growth and flowering of potted Chrysanthemum morifolium Ramat cv. Snowball. Plants were grown in six different potted medium compositions - control: garden soil + (farmyard manure (FYM) 2: 1), cocopeat + FYM (1: 1), cocopeat + FYM (2: 1), vermiculite + FYM (1: 1), vermiculite + FYM (2: 1) and cocopeat + vermiculite + FYM (1: 1: 1). Results revealed vegetative growth with maximum plant height, number of leaves and root suckers per plant in the case of cocopeat + FYM (2: 1), whereas flower quality, i.e. duration of flowering and flower diameter was highest in media vermiculite + FYM (2: 1). Moreover, plants showed significant (P < 0.05%) vegetative growth with better flowering time and quality in cocopeat + vermiculite + FYM (1: 1: 1). Therefore, the present findings suggest that for growing potted chrysanthemum cv. Snowball for display, light-weight growing medium composition of cocopeat + vermiculite + FYM (1: 1: 1) is the best with better plant morphological development and sustained quality flower production.

The study was conducted to determine the effect of duration of night interruption using incandescent bulbs on sustained quality flower production of potted standard Chrysanthemum cv. Kikiobiory. The different night interruption (NI) treatments i.e. control, <5 sec. flash, 30-, 60-, 90- and 120- min. significantly (p<0.05) affected allthe vegetative and floral parameters. The plant height, number of leaves and root suckers per plant increased with the increase duration of NI treatments with maximum at 120- min. NI (90.42 cm, 34.75 and 12.10, respectively). The days taken to flower bud appearance, colour break stage and full bloom were delayed, whereas flower quality with respect to duration of flowering and flower diameter were deteriorated with increase in duration of NI treatments. The days taken to flower bud appearance, colour break stage and full bloom were highest at 120- min. NI (136.84, 183.22 and 202.25 days, respectively) which delayed the flowering by 63.94 days, where full bloom flower appeared in March. There was reduction in duration of flowering and flower diameter with increased NI duration with lowest at 120 min. NI (7.83 days and 15.69 cm). It was observed that increase (120 min.) in night interruption increased the vegetative growth and delayed the flowering; however, flower quality was deteriorated. Thus, it was concluded that 60 min. NI improved flower quality with sustained flower production in potted Chrysanthemum cv. Kikiobiory.

The effect of nitrogen doses on growth and flowering of chrysanthemum (Chrysanthemum morifolium Ramat) cv. Anmol was evaluated in a pot study conducted in 2014–16 at Ludhiana. The nitrogen (@ 0,100, 200, 300, 400 and 500 mg Urea/pot) to Chrysanthemum plants was applied in two splits in mid-September and mid-October. The application of all nitrogen levels had significant effect on the vegetative and floral parameters like plant height, number of primary branches, leaves, root suckers, flowers per plant, size of flower and delayed days taken to full bloom, however doses beyond 300 mg Urea/pot deteriorated the flower quality with respect to duration of flowering. Therefore, it was concluded that optimum nitrogen application for quality flower pot production was 300 mg Urea/pot.