Effect of temperature, daylength and light intensity on growth and development of Dipladenia sanderi Hemsl. ‘Rosea’

As a basis for breeding cvs adapted to flowering in winter light conditions, the growth of hybrid tea rose seedlings under controlled conditions was studied. Irradiance varied from 4-24 W/m2, day length was 8 h, temperature 21 deg C. Like cvs, the seedlings sometimes aborted the flower bud at low light intensity. With increasing irradiances, the following phenomena were observed: the juvenile period of the seedlings shortened; plants were longer at bud formation, at first flowering and at flower bud abortion; leaf area and the number of petals increased. Leaf number was constant at all irradiances. Flowering seedlings were smaller at bud formation, but taller at actual flowering than blind ones. Blind seedlings had fewer leaves with a smaller area. (Abstract retrieved from CAB Abstracts by CABI’s permission)

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THE CONTROL OF GROWTH AND DEVELOPMENT IN RED CLOVER (TRIFOLIUM PRATENSE L.): II. LIGHT, TEMPERATURE, AND THE INFLUENCE OF GROWTH REGULATORS

Canadian Journal of Botany ◽

10.1139/b59-082 ◽

1959 ◽

Vol 37 (5) ◽

pp. 1027-1048 ◽

Cited By ~ 4

Author(s):

Bruce G. Cumming

Keyword(s):

Light Intensity ◽

Growth Regulators ◽

Growth And Development ◽

Trifolium Pratense ◽

Stem Elongation ◽

Indirect Evidence ◽

Continuous Light ◽

Red Clover ◽

Auxin Level ◽

Increased Sensitivity

Morphogenesis of Dollard red clover clones has provided indirect evidence that endogenous auxin level and, or, sensitivity of response of tissues to auxin vary according to light and temperature and as a function of genotype.The amount of growth and development was less in autotetraploid than in diploid plants.Root formation on propagules was influenced by relatively short-term different daylength pretreatments of intact plants; also, by the daylength and light intensity imposed during rooting.Under reduced light intensity extension growth already initiated was increased and this was related to increased "sensitivity" of growth response of stems and petioles to applied auxin.Morphogenetic effects relatively similar to those caused, respectively, by shortening the daylength and by lengthening the daylength resulted from antiauxin (TIBA) as compared with auxin (IAA) treatments.Concentrations of IAA that were primarily stimulatory to growth under shorter daylengths were inhibitory under continuous light. The primary stimulatory effect of IAA was on bud formation under SD but on stem elongation under LD.The relatively similar and additive effects of photoperiod, applied auxin, and cold pretreatment are discussed. It is postulated that in red clover a greater endogenous diffusible auxin level is required for optimum formation of stems and inflorescences than for buds and roots.Manipulation of light and temperature and the use of growth regulators provide added precision in the control of growth and development in red clover.

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The effect of temperature on growth and development of cultivars of radish under winter conditions

Scientia Horticulturae ◽

10.1016/0304-4238(76)90073-x ◽

1976 ◽

Vol 5 (2) ◽

pp. 111-118 ◽

Cited By ~ 4

Author(s):

M. Nieuwhof

Keyword(s):

Growth And Development ◽

Effect Of Temperature ◽

Winter Conditions

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Seed germination ecology of Sumatran fleabane (Conyza sumatrensis) in relations to various environmental parameters

Weed Science ◽

10.1017/wsc.2021.56 ◽

2021 ◽

pp. 1-26

Author(s):

Gulshan Mahajan ◽

Asheneel Prasad ◽

Bhagirath Singh Chauhan

Keyword(s):

Seed Germination ◽

Light Intensity ◽

Chloride Concentration ◽

Soil Surface ◽

Control Treatment ◽

Effect Of Temperature ◽

Burial Depth ◽

Germination Ecology ◽

Wide Range ◽

Dark Conditions

Abstract Sumatran fleabane [Conyza sumatrensis (Retz.) Walker] is an emerging weed in the Australian cropping region. Populations resistant to glyphosate have evolved in Australia, creating the demand for information regarding the seed germination ecology of glyphosate-resistant (R) and glyphosate susceptible (S) populations of C. sumatrensis. A study was conducted to examine the effect of temperature, light intensity, salt stress, osmotic stress, and burial depth on the germination and emergence of two populations (R and S) of C. sumatrensis. Both populations were able to germinate over a wide range of alternating day/night temperatures (15/5 to 35/25 C). In light/dark conditions, the R population had higher germination than the S population at 20/10 and 35/25 C. In the dark, the R population had higher germination than the S population at 25/15 C. In the dark, germination was inhibited at 30/20 C and above. Averaged over populations, seed germination of C. sumatrensis was reduced by 97% at zero light intensity (completely dark conditions) compared with full light intensity. Seed germination of C. sumatrensis reduced by 17 and 85% at an osmotic potential of −0.4, and −0.8 MPa, respectively, compared with the control treatment. The R population had lower germination (57%) than the S population (72%) at a sodium chloride concentration of 80 mM. Seed germination was highest on the soil surface and emergence was reduced by 87 and 90% at burial depths of 0.5 and 1.0 cm, respectively. Knowledge gained from this study suggests that a shallow-tillage operation to bury weed seeds in conventional tillage systems, and retention of high residue cover in a zero-till system on the soil surface may inhibit the germination of C. sumatrensis. This study also warrants that the R population may have a greater risk of invasion over a greater part of a year due to germination over a broader temperature range.

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The Influence of Temperature and Humidity on Instar Length in Calandra Granaria Linn

Journal of Experimental Biology ◽

10.1242/jeb.24.1-2.79 ◽

1947 ◽

Vol 24 (1-2) ◽

pp. 79-94

Author(s):

L. E. S. EASTHAM ◽

F. SEGROVE

Keyword(s):

Growth And Development ◽

Effect Of Temperature ◽

Threshold Temperature ◽

Food Utilization ◽

Optimum Temperature ◽

Atmospheric Humidity ◽

Larval Instars ◽

Balance Sheets ◽

Temperature And Humidity ◽

Effects Of Temperature

1. The effects of temperature and humidity on the duration of each instar of the life cycle of Calandra granaria Linn. have been examined. The insects were reared at temperatures ranging from 15 to 30° C. and at atmospheric humidities ranging from 40 to 80% R.H. 2. A method is described for assessing the effect of temperature as an independent factor. 3. The temperatures employed fall within the ‘vital zone’. Extrapolation indicates the threshold temperature to be approximately 11° C. for the egg and larval instars though somewhat lower for the pupa. 30° C. is below the optimum temperature. 4. The durations of the egg and pupal stages are not affected by atmospheric humidity. 5. The duration of all larval instars is affected by moisture. It is suggested that this is largely due to atmospheric humidity and that food water is of little significance. 6. Shortage of moisture acts as an obstacle to development. Evidence is presented which indicates that drier atmospheres tend to desiccate the insect and that desiccation is responsible for retarded growth and development. 7. Since much earlier work on temperature and moisture has been done on fasting insects and, therefore, on insects deficient in one of the most important environmental factors, we suggest that our results, incomplete as they are, indicate the need for new approaches to be made. More complete data on feeding insects under controlled conditions of food, temperature and moisture are required, from which can be drawn up more complete balance sheets of development involving measurements of food utilization and respiratory rates.

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