Leaf Status and Photoperiodic Control of Flower Initiation in a Late Variety of Pea

Nature ◽  
1967 ◽  
Vol 215 (5098) ◽  
pp. 319-320
Author(s):  
D. M. PATON
1985 ◽  
Vol 65 (4) ◽  
pp. 995-1000
Author(s):  
JOHN SIMMONDS

The influence of photoperiod and temperature on the production of flowers by a New Guinea hybrid Impatiens, cv. Starburst, was investigated. Delayed flowering below 20 °C was due only to effects on flower bud development. Although flower initiation was day-neutral, the number of flowers produced was significantly influenced by photoperiodic control of axillary branch elongation. In 8-, 14- or 16-h photoperiods axillary branches on the lower nodes remained compact but in a 12-h photoperiod the axillary branches elongated, and flower production on these axillary branches was enhanced. Night-break (NB) treatments indicated that this was a photoperiodic effect. This photoperiodic control of plant growth habit provides a means of regulating the rate of flowering of this cultivar.Key words: Impatiens, photoperiod, flowering, apical dominance


1982 ◽  
Vol 60 (4) ◽  
pp. 320-324
Author(s):  
John Simmonds

The effects of photoperiod and temperature on flower initiation and the rate of node production in a New Guinea hybrid Impatiens cv. Starburst were investigated. The node of first flower initiation was not a reliable estimate of the time of flower initiation unless treatment influences on the rate of node production were also considered. Plants maintained at 25 °C responded as quantitative short-day plants; the time of flower initiation was earlier, and the degree of flowering was greater, in 8- and 14-h photoperiods than in 18-h photoperiods. In short (12-h) photoperiods flowering was modulated by temperature. The time of flower initiation was reduced from 27 days at 25 °C to 13 days at 20 °C and to 10 days at 15 °C. Night-break experiments indicated that flowering at 25 °C was subject to photoperiodic control but at 15 °C the plants were "day-neutral."


1996 ◽  
Vol 98 (3) ◽  
pp. 564-570 ◽  
Author(s):  
Ivana Machackova ◽  
Josef Eder ◽  
Vaclav Motyka ◽  
Jan Hanus ◽  
Jan Krekule

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 509a-509
Author(s):  
C.E. Wieland ◽  
J.E. Barrett ◽  
D.G. Clark ◽  
G. J. Wilfret

Four poinsettia cultivars were grown in glass greenhouses in Gainesville, Fla., in the Fall 1997 to evaluate differences in floral initiation and subsequent development. Three means of regulating photoperiod were 1) natural days 2) long-day lighting to 6 Oct. and then natural days (lights out) 3) long-day lighting to 6 Oct., and then short-day conditions by black cloth for 15 h (black cloth). At 2-day intervals, sample meristems were collected and examined for initiation of reproductive development. Average minimum and maximum temperatures during the first two weeks of October were 22 and 29 °C, respectively, with an average temperature of 25.3 °C. The overall average temperature was 23.2 °C from planting to anthesis. Differences in anthesis dates among cultivars were primarily due to time to initiation vs. rate of development. Under natural days, `Lilo' initiated first on 8 Oct. and `Freedom', `Peterstar', and `Success', followed by 6, 8, and 18 days, respectively. Lights out resulted in `Lilo' initiating 17 Oct., followed by `Freedom', `Peterstar', and `Success' initiating 7, 12, and 15 days later, respectively. Differences between cultivars in time of initiation was reduced under black cloth, where `Lilo' initiated 14 Oct., followed by `Freedom' 2 days later, and `Peterstar' and `Success' 7 days afterward. Initiation was positively correlated to visible bud and anthesis. First color was positively correlated to initiation and visible bud, with the exception of `Lilo'. Growth room studies conducted using various high temperatures and photoperiods indicated similar trends.


2021 ◽  
Vol 13 (4) ◽  
pp. 1985
Author(s):  
Musa Al Murad ◽  
Kaukab Razi ◽  
Byoung Ryong Jeong ◽  
Prakash Muthu Arjuna Samy ◽  
Sowbiya Muneer

A reduction in crop productivity in cultivable land and challenging environmental factors have directed advancement in indoor cultivation systems, such that the yield parameters are higher in outdoor cultivation systems. In wake of this situation, light emitting diode (LED) lighting has proved to be promising in the field of agricultural lighting. Properties such as energy efficiency, long lifetime, photon flux efficacy and flexibility in application make LEDs better suited for future agricultural lighting systems over traditional lighting systems. Different LED spectrums have varied effects on the morphogenesis and photosynthetic responses in plants. LEDs have a profound effect on plant growth and development and also control key physiological processes such as phototropism, the immigration of chloroplasts, day/night period control and the opening/closing of stomata. Moreover, the synthesis of bioactive compounds and antioxidants on exposure to LED spectrum also provides information on the possible regulation of antioxidative defense genes to protect the cells from oxidative damage. Similarly, LEDs are also seen to escalate the nutrient metabolism in plants and flower initiation, thus improving the quality of the crops as well. However, the complete management of the irradiance and wavelength is the key to maximize the economic efficacy of crop production, quality, and the nutrition potential of plants grown in controlled environments. This review aims to summarize the various advancements made in the area of LED technology in agriculture, focusing on key processes such as morphological changes, photosynthetic activity, nutrient metabolism, antioxidant capacity and flowering in plants. Emphasis is also made on the variation in activities of different LED spectra between different plant species. In addition, research gaps and future perspectives are also discussed of this emerging multidisciplinary field of research and its development.


Processes ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 420 ◽  
Author(s):  
Shashidhar K. Shankarappa ◽  
Samuel J. Muniyandi ◽  
Ajay B. Chandrashekar ◽  
Amit K. Singh ◽  
Premaradhya Nagabhushanaradhya ◽  
...  

Lentil (Lens culinaris) is an important winter season annual legume crop known for its highly valued seed in human and animal nutrition owing to its high lysine and tryptophan content. Shortage of water during the crop growth period has become the major impediment for cultivation of pulses in rice fallow in particular. Under such conditions, the application of hydrogel can be a potential alternative to improve photosynthetic efficiency, assimilate partitioning, and increase growth and yield. A field experiment was conducted from November to February during 2015–16 to 2017–18 on clay loam soil that was medium in fertility and acidic in reaction (pH 5.4) at Central Agricultural University, Imphal, Manipur. The experiment was laid out in split plot design with three replications. There were three hydrogel levels in total in the main plot and foliar nutrition with five different nutrient sprays in sub-plots, together comprising 15 treatment combinations. The data pooled over three years, 2015–2018, revealed that application of hydrogel at 5 kg/ha before sowing recorded a significantly greater number of pods per plant (38.0) and seed yield (1032.1 kg/ha) over the control. Foliar application of nutrients over flower initiation and pod development had a positive effect on increasing the number of pods per plant eventually enhanced the seed yield of lentil. Foliar application of either 0.5% NPK or salicylic acid 75 ppm spray at flower initiation and pod development stages recorded significantly more pods per plant over other nutrient treatments. Further, the yield attributed improved because of elevated growth in plant. Significantly maximum seed yield (956 kg/ha) recorded in the NPK spray of 0.5% remained on par with salicylic acid 75 ppm (939 kg/ha) over the rest of the treatments.


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