Heat and Growth

Day: Temperature and Barley Germination (1891)

Plumb: Germination temperature of maize (1895)

Greeley: Temperature and Rose Bloom (1919)

Greeley: Night-Growth of Roses (1920)

MacDaniels: Fruit bud formation in Rubus and Ribes (1922)

Risley: Male Controls Sprouting in Rose Seeds (1958)

Boodley & Seeley: Effects of night temperatures on growth of roses (1960)

Semeniuk: Temperature and Rose fertility (1964)

Moe & Kristofferson: Temp & Light & Roses (1969)

Moe: Daylength, Temp Effects on Roses (1972)

Jinks & Connolly: Selection for temperature response (1973)

Jerabek: Breeding Yellow Hybrid Tea Roses (1975)

Collinson: Temperature and tolerance range of plants (1988)

Moe: Growth and Flowering in Roses (1988)

Allen: Rosa arvensis, A problem Wild rose. (1987)

Hodges: Thermal Time Accumulation in plants (1991)

Plants in Action: Adaptation in Nature, Performance in Cultivation (1999) p. 446

Temperature effects on growth can be viewed in relation to either rate of organ production or the final size attained. Size results from both rate and duration of growth, and there are many examples where organ size is reduced at high temperature because rate of growth cannot compensate for a reduced duration of growth. This is illustrated for wheat (a temperate cereal) and rice (a subtropical cereal). At low temperature wheat has a much larger grain than rice, but rice has a much more stable grain size than wheat in relation to temperature and at 30°C grain size in the two species is similar.

Takatsu, et al.: Temperature Effects on Interspecific Hybridization between Gladiolus x grandiflora and, G. tristis. HortScience 36(2):341-343. 2001.

Naor: Temperature affects development, flowering dormancy in Calla (2002)

Carvalho, et al: Effect of day and night temperature on internode and stem length in chrysanthemum (2002)

Cornejo: Calla, heat, bud dormancy (2003)

Ngamau: Selection for early flowering, temp. and salt tolerance, Calla (2006)
Abstract: Zantedeschia, an important cut flower that shows high variability in plant height, flowering period and other characteristics when grown from seeds. Availability of variability, however, provides opportunity for the selection for such characteristics as early flowering, temperature or salt tolerance. In-vitro germination may be utilized in the selection for early germination under unfavourable conditions and selected seedlings rapidly multiplied by multiple shoot formation. This study described the selection procedures using early germinating seeds of Zantedeschia 'Green Goddess' on their flowering time, temperature and salt tolerance. The seeds were sown on in-vitro Murashige and Skoog (MS) medium at 20°C and 16h light; early germinating seeds transferred singly to new medium. For temperature tolerance, seeds were sown on media maintained at 10, 15 and 20°C. For salt tolerance, seeds were sown on medium containing 0, 40, 80, 120, 160 and 200 mmol/L NaCl. The selected seedlings were then multiplied in-vitro to develop clones, which were tested for flowering, temperature tolerance and salt tolerance against clones which germinated later. The results showed that clones, which were selected from early-germinated seedlings, grew faster, flowered earlier and produced more flowers than clones that germinated later. Early germinated seedlings at low temperatures achieved greater growth at lower night temperatures than those germinated at high temperatures. Clones selected after germination at higher levels of sodium chloride (NaCl) attained greater growth on media containing salt than those that germinated on salt free medium.

Meyer: Germination of Rose seeds (2008)

Heat and Development

Knight: Excessive Heat in Forcing-houses (1814)

Knight: Effects of high temperature on plants (1819)

Cook: Cuzco Corn (1916)

Griffiths & Wright: Temperature and Narcissus (1932)

Peto: Aging, heat and mutations in corn and barley (1933)

Jones: Maize and Heat (1947)

Went: Thermoperiod (1948)

Highkin: Temperature-Induced Variability in Peas (1958)

Lyubimova: Overcoming sterility in hybrids (1960)
By providing optimum temperatures and other optimum environmental conditions during meiosis, the postmeiotic development of the sex cells, and during flowering and fertilization, one can in many cases raise a very low fertility and sometimes even overcome the sterility of wide hybrids.
    The material which we have discussed briefly shows that there are different means for overcoming the sterility and increasing the fertility of wide hybrids. Further investigations in this direction, based on the achievements of biology and making use of the most up-to-date methods, will undoubtedly enable us to overcome hybrid sterility with even greater success. This will widen the scope for obtaining hybrids between even more remote plants and for creating valuable new plant species.

Semeniuk: An effect of temperature on development and differentiation of rose flowers. (1964)
More petals and bigger blooms were produced on glasshouse roses of the variety Ma Perkins grown at lower temperatures (62 degrees and 72 degrees F.) than on those grown at higher temperatures. At 82 degrees and 92 degrees F. the number of petals was reduced to the basic 5.

Moe & Kristofferson: Temp & Light & Roses (1969)

Delp: Heat in Hybridizing Rhododendrons (1980)

Moe: Growth and Flowering in Roses (1988) Higher temperatures, fewer petals.

de Munk: Thermomorphogenesis in Bulbous Plants (1989)

Gudin: Influence of bud chilling on subsequent reproductive fertility in roses (1992)
Pot plants of Rosa hybrida L. cultivar ‘Meijikatar’ were submitted or not to a 1 month cold treatment just after cut-back. After subsequent culture in a greenhouse, the treatment resulted in an improved production of flowers, hips and seeds resulting either from self- or cross-pollinations. It also determined a specific morphology of the styles and an improved in vitro elongation of the pollen tubes. The cold pre-treatment effect could be explained by its influence on fertility. This influence, although diminishing, could still be demonstrated after pollination on the second flush of flowers.

Patricia Routley (HelpMeFInd, 3 Jan 2013): After a wonderfully wet spring, then a horrific heatwave lasting 5 or 6 days, and returning at last to 2 cool and most pleasant days. 'Agnes' has gone semi-double and pinkish apricot.

The Indian Gardener, Volume 1: 288 (July 7, 1885)
B. S. H.
Rose Edouard, a grand old Rose in itself, as regards habit, is better adapted as a stock for general propagation than the preceding [Rosa gigantea]; it has, however, one unfortunate defect, which it too frequently transmits to the plants worked on it, that is, that during the cold season it almost invariably refuses to expand its blooms.

A Manual of Gardening for Bengal and Upper India, pp. 475-477 (3rd edition) (1874)
Thomas Augustus Charles Firminger
1. ROSE EDOUARD.—Originally from the Isle of Bourbon, and parent of the whole group. An old well-known Rose in all parts of India, most desirable for the constancy of its bloom as well as for the sweetness of its flowers; during the Cold season it produces flower-buds in unbounded profusion, which rot in the centre, and never open. The stems after blossoming should be pruned in closely. Exceedingly vigorous in growth, and easily propagated, affording the best stocks we have for budding other kinds upon.