scholarly journals Growth Response of 20 Seed Geranium Cultivars to Three Day–Night Temperature Regimes

HortScience ◽  
1995 ◽  
Vol 30 (7) ◽  
pp. 1465-1466
Author(s):  
Mark S. Strefeler

The influence of temperature and genotype on plant height, internode length, and morphological development of 20 cultivars of Pelargonium ×hortorum Bailey were determined by growing plants under one of three day–night temperature regimes (18/18C, 18/24C, and 24/18C). Temperature regime influenced internode length and plant height regardless of plant genotype. Internode length and plant height increased as the day–night temperature differential (DIF) increased from –6 to 6C. Average internode length increased from 5.3 ± 0.2 mm for –6C DIF to 6.3 ± 0.2 mm for +6C DIF. Genotypes differed for average internode length (4.2 to 8.7 mm) and plant height (54 to 95 mm). Node count increased as average daily temperature (ADT) increased. Node counts were 11.2 at 18/18C (ADT = 18), 11.9 at 24/18C (ADT = 20.3), and 12.1 at 18/24C (ADT = 21.8). Genotype × temperature interactions were not significant for the recorded traits. This study demonstrates that DIF is an effective height control strategy, regardless of geranium genotype, and that DIF combined with the selection of genetically short cultivars may eliminate the need for chemical height control in the commercial production of geraniums.

1998 ◽  
Vol 8 (4) ◽  
pp. 535-539 ◽  
Author(s):  
Robert Berghage

Temperature management has emerged as an important tool for plant height control in greenhouse production systems. This is particularly important in vegetable transplant production where chemical controls for plant height are limited or not legal. Plant height is a function of the number of nodes and the length of each internode, and both are strongly influenced by greenhouse temperatures. Node number, or formation rate, is primarily a function of the average greenhouse temperature, increasing as the average temperature increases. Internode length is strongly influenced by the relationship between the day and night temperature, commonly referred to as DIF (day temperature - night temperature). As DIF increases, so does internode length in most plant species studied. Although the nature and magnitude of temperature effects vary with species, cultivar, and environmental conditions, these two basic responses can be used to modify transplant growth. Although data are limited, controlling transplant height with temperature does not appear to adversely influence plant establishment or subsequent yield.


HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 862B-862
Author(s):  
Yaping Si ◽  
Royal D. Heins

Sweet pepper (Capsicum annuum `Resistant Giant #4') seedlings were grown in 128-cell plug trays under 16 day/night temperature (DT/NT) regimes from 14 to 26C. In this temperature range, plant stem height, leaf unfolding rate, plant volume, internode length, stem diameter, leaf area, and shoot dry weight were primarily functions of average daily temperature (ADT). Internode length increased as ADT or the difference between day and night temperature (DIF) increased. The root-to-shoot ratio decreased linearly as DT increased and was not significantly affected by NT. Leaves were darker green under positive DIF than negative DIF temperature regimes. Increasing NT from 14 to 26C reduced the node at which the first flower appeared by an average of 1.2 nodes. Percent abortion of the first flower increased as DT increased. Plant quality, as defined by seedling index [(dry weight × stem diameter)/internode length], increased as DIF became more negative.


HortScience ◽  
1992 ◽  
Vol 27 (3) ◽  
pp. 216-217
Author(s):  
Serge Gagnon ◽  
Blanche Dansereau

Geranium seedlings (Pelargonium ×hortorum Bailey `Smash Hit Red') were given various cold pretreatments (CP) to obtain more rapid adaptation to constant or split-night temperature regimes. The six following CP were used: either 13C or 17/13C for 5, 10, or 15 days. The effect of these CP given at seedling stage was compared with that of control plants held at 17C at night. The CP did not significantly increase the time to first visible flower buds or to anthesis. The number of flowering stems, plant height, shoot dry weight, and leaf area of control plants were not significantly different from plants receiving CP.


2016 ◽  
Vol 29 (4) ◽  
pp. 841-849
Author(s):  
ADRIANA QUEIROZ DE ALMEIDA ◽  
SIMONE ALVES SILVA ◽  
VANESSA DE OLIVEIRA ALMEIDA ◽  
DEOCLIDES RICARDO DE SOUZA ◽  
GILMARA DE MELO ARAÚJO

ABSTRACT The knowledge about genetic diversity of jatropha crop is important for genetic conservation resources and breeding of this species. The aim of this study was to evaluate the genetic diversity and performance of jatropha clones through morphological characterization to selection of clonal varieties for biofuels production. The clones were obtained through shoot cuttings from previous selection in a population of half-sibs progenies. The morphoagronomic analyses of clones was carried out at 180 days after transplantation and were evaluated plant height, stem diameter, number of primary branches and number of secondary branches, number of bunches and number of fruits per plant. Evaluating clones performance, significant results were found for the number of secondary branches. About analysis of genetic diversity, the measures of dissimilarity genetic varied from 0.62 to 13.11, this way, the UFRBPR14 and UFRBPR15 clones were more divergent. The Tocher method was efficient to verify formation of four groups. The characteristics that most contributed to the divergence among clones were branches number, height and number of bunches, and, stem diameter had lower contribution. The jatropha clones differed only in the secondary branches number and multivariate analysis showed divergence among the jatropha clones with formation of four groups. Also, branches number, plant height and number of bunches were characteristic that contributed to genetic divergence.


2019 ◽  
pp. 48-52
Author(s):  
S. K. Shchukis ◽  
E. R. Shchukis

The article emphasizes the importance of peas as a source of vegetative protein, and indicates on insufficient areas under peas both in Russia and in the Altai. One of the reasons of reducing its acreage is the high costs on peas planting and protecting from pests, diseases and weeds. Climate changing contributes to rapid development of such harmful diseases as ascohitoz, bacteriosis, fusarium, rust, significant number of weevil, pea aphid and moth mullet. Considering the main directions in pea breeding, it should be emphasized that the Altai Area, with its vast territory and diverse natural and climatic conditions, requires highly productive, well-adapted varieties of different use which are capable to effectively use agro-climatic resources of different zones. All this requires the active study of the source material, the selection of new, economically valuable forms and their introduction into the breeding process. It has been noted that the production requires more advanced varieties, the development of which is impossible without the presence of diverse source material. The purpose of the study was to identify the best productive plants in the pea collection of 2012-2017. The material has been represented by 113 variety samples of domestic and foreign selection. The varieties with best productivity were ‘Mnogoplodny 163’, ‘Rheinperle’, ‘Flagman 12’, ‘806’9, ‘Varyag’, ‘Altaisky Usaty’, ‘Pioner’, ‘LittleMarwel’, ‘Mnogoplodny 27’, ‘Zeleny Tsukat’, ‘Ryadovoy’, ‘576/80’. The best forage productivity was produced by ‘Novosibirets’, ‘Varyag’, ‘Pino’, ‘Zeleny Tsukat’, ‘Mnogoplodny 105’. The most fast-ripening varieties were ‘Rheinperle’ and ‘Pyrama’. The samples ‘Novosibirets’, ‘Varyag’, ‘Pino’ and ‘8067’ were characterized with high plant height. The samples ‘Pyrama’, ‘Flagman 12’, ‘Novosibirets’, ‘Sihirobana-Kinusaja’, the line ‘312’ produced large-sized kernels. The great lodge resistance has been shown by ‘Altaisky Usaty’, ‘Svetozar’, ‘Kamerton’, ‘Flagman 12’.


2020 ◽  
Vol 5 (01) ◽  
pp. 45-49
Author(s):  
Ankit Kumar ◽  
Amit Tomar

The results revealed that parents namely, TSK-10, TSK-27, New Blue-II, Kurara and TSK-109 were found highly genetic diverse for days to 50% tasseling, days to 50% silking, days to 755 dry husk. The parents namely, TSK-109, Kurara, New Blue-II and TSK-10 were found highly genetic diverse for plant height (cm), cob height, number of cobs per plant and number of grains per cob. The parents namely, Kurara, TSK-109, TSK-10, New Blue-II and TSK-27 were found highly genetic diverse for shelling percentage, grain yield per plant, grain yield per cob and 100-grain weight.


2017 ◽  
Vol 45 (1) ◽  
pp. 1-8
Author(s):  
Gerland Akhmadi ◽  
Bambang Sapta Purwoko ◽  
Iswari Saraswati Dewi ◽  
Dan Desta Wirnas

Anther culture technique is able to accelerate plant breeding activities. The objectives of this research was to determine the agronomic traits that could be used for selection of the dihaploid rice line population through the calculation of heritability, genotypic correlation, path analysis and selecting dihaploid rice lines. The plant material used was 65 dihaploid rice lines DH 1 of F1 anther culture plants and Ciherang and Inpari 13 as check varieties. Agronomic characters that could be used as selection character are generative plant height, number of filled grain per panicle, the total number of grains per panicle, weight of 1,000 grains, and grain per hill. Twenty three dihaploid lines were selected based good agronomic characters with criteria generative plant height between 80-120 cm, number of filled grains per panicle > 100, number of grains per panicle > 120, weight of 1,000 grains > 20 g, and grain per hill > 25 g.Keywords: anther culture, heritability, agronomic characters


1965 ◽  
Vol 16 (1) ◽  
pp. 1 ◽  
Author(s):  
RD Asana ◽  
RF Williams

Experiments were conducted in controlled environments to determine the effects of high temperatures on grain development and yield in wheat. Two Australian and three Indian cultivars of wheat were exposed, from a week after anthesis until maturity, to "day" temperatures of 25, 28, and 3l°C, and "night" temperatures of 9 and 12°C. There was a mean reduction in yield of 16%' for the 6° rise in day temperature, but the cultivars did not differ significantly in their response to these temperatures. There were no significant effects of night temperature on grain weight, but stem weight was less at 12°C. Senescence was hastened only slightly by high day temperature, and there were no differential effects between cultivars in this respect.In a subsidiary experiment one Indian and five Australian cultivars were subjected to three day-night temperature regimes (24/19°, 27/22°, and 30/25°C). Highly significant but complex interactions were established between temperature regime and cultivar. A growth analysis for the Australian cultivars Ridley and Diadem indicated that the developing grain of Ridley had a greater capacity for growth than that of Diadem from the earliest stage. This, together with the confirmation of grain size as a very stable characteristic for all the varieties, points to the developmental and synthetic activity of the grain as an important determinant of grain yield. The relevance of this study to the production of wheat in India is briefly discussed.


1990 ◽  
Vol 70 (3) ◽  
pp. 925-930 ◽  
Author(s):  
PETER R. HICKLENTON

This study investigated the effects of growth retardants uniconazole [(E) - (p-chlorohenyl) -4, 4-dimethyl-2-(1,2,4-triazol-1-yl)-1-penten-3-ol] and daminozide (butanedioic acid mono 2,2-dimethylhydrazide) on three chrysanthemum (Dendranthema grandiflora Tzvelev.) cultivars. Uniconazole applied as a soil drench (0.02 mg a.i. pot−1) or foliar spray (0.014 mg a.i. pot−1) 10 d after removal of the shoot tip reduced plant height at harvest in cultivars Deep Luv, Tip and Tara. Higher doses of uniconazole resulted in further plant height reduction in Tip and Tara but not in Deep Luv. Daminozide spray (14 mg a.i. pot) and uniconazole spray (0.028 or 0.056 mg a.i. pot−1) produced plants of similar height. Pre-plant dips of both growth retardants were less effective than sprays or drenches in controlling height. Flower area and flower dry weight were reduced with uniconazole drench and spray, and daminozide spray in each cultivar. Shoot dry weight was similarly affected in Tip and Tara but not in Deep Luv. Flowering was delayed in each cultivar by post-plant treatments of uniconazole drench and spray and by daminozide spray (0.08, 0.014 and 14 mg a.i. pot−1, respectively), and by daminozide and uniconazole pre-plant dips (5.0 mg L−1 and 4000 mg L−1, respectively).Key words: Sumagic, XE-1019, B-Nine, Alar, Chrysanthemum × morifolium, Dendanthema grandiflora


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