Agriculture Reference
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to their unfavorable intervention in the requirements of drought stress in
the tropics while, low temperature in the subtropics; occurrence of frost
(-0.2 °C to −1.2 °C on 9th and 10th January, 2013) as it happened at CISH,
Lucknow howevervirtually killed a portion of the shoots and triggered
the emergence of new vegetative flushes from the lateral buds subtend-
ing the dead portion of shoots, thus contributing to transgression of tree
physiology from an expected reproductive one predominantly. Perhaps
this was also compounded by the occurrence of hailstorm on 18th and
19th January 2013. Such a situation altered the dynamics of trips incidence
in several cases, resurgence on new vegetative flushes despite spraying of
thiomethoxam (0.02%) and in some instances, damages to the fruits at pea
stage of development. Temperature dynamics together with soil moisture
conditions (due to unseasonal rainfall that occurred on 18 and 19th Janu-
ary, 2013) that prevailed during 2013 witnessed however, below threshold
levels incidence of mealy bugs, hoppers and powdery mildew. Summary
responses of different phenophases to weather variables across standard
meteorological weeks and their implications in inciting production con-
straints of '
Dashehari
' during 2010-12 are indicated in
Table 5.2.
5.2.1.3
PHYSIOLOGICAL ATTRIBUTES
Under subtropical conditions, flowering in mango is influenced by cool
temperatures, although the temperatures reported for cold induction in
mango are much higher than those reported for vernalization. Vegetative
growth in mango is through episodic flushing, which was more frequent
as per temperature increases recorded during 2013 fruiting season in the
Lucknow region.
Mango being a C
3
plant, the photosynthetic performance among cul-
tivars is important for productivity under variable climatic conditions.
Higher photosynthetic efficiency during reproductive phenophases es-
pecially flowering and fruit growth was identified as the important traits
contributing to higher productivity. Under Lucknow conditions photosyn-
thetic fluxes under different temperature regimes in 25 cultivars represent-
ing different agro-climatic regions of the country was evaluated (Singh
and Rajan, 2009) where in the commercial cultivars of Lucknow region
were found more efficient as compared to others. Precise understanding of
