Book of Extended summaries ISDA

International Conference on Reimagining Rainfed Agro-ecosystems: Challenges &
Opportunities during 22-24, December 2022 at ICAR-CRIDA, Hyderabad
diseases and weather parameters like temperature and relative humidity influence flowering
and fruit set in mango. Hence a study was conducted to establish a relationship of weather
parameters with the flowering behaviour and yield of mango using per cent hermaphrodite
flowers, fruit set (%) and fruit yield of mango.
Methodology
The present investigation was executed at 2 locations/orchards with two management levels
(M1: control and M2: With Plant Protection Chemicals) with a sample size of 5 plants each in
2 locations with different age groups (20 and 28 years old plantation) located at Dryland
Agriculture Project, Zonal Agricultural research station, UAS, GKVK, Bengaluru analysed
using factorial RCBD for two years (2020-21 and 2021-22). To manage the major diseases
and pests like powdery mildew, anthracnose, fruit fly and mango hoppers two sprays were
given to the spray treatment trees with Hexaconazole @ 5 % SC, Lambda Cyhalothrin @ 5 %
EC and Sulphur @ 80% WP at the time of flower bud initiation and fruiting stage.
Observations are recorded from the start of vegetative growth, and flowering till the
harvesting of fruits.
Results
The per cent hermaphrodite flowers from the number of hermaphrodite flowers to the total
number of flowers per panicle in each direction in Mallika hybrid was higher in 20 years old
(24.0 %) with spray treatment (24.2 %) in the north direction of the tree (24.6 %) (Table 1).
This may be due to the higher proportion of hermaphrodite flowers in the 20 years old tree
and male flowers being more than bisexual flowers and along with the flowering behaviour, it
was also affected by the temperature. Both male and hermaphrodite flowers are found within
a single inflorescence. It is the hermaphrodite flowers that often undergo proper pollination
and fertilization and set fruit. Low temperature during the floral morphogenesis period which
is much before the flower emergence is critical for the proportion of hermaphrodite flowers in
mango. Flower bud differentiation in different cultivars and seasons was associated with
higher chlorophyll, carbohydrate and carbohydrate-nitrogen ratio, total phenol, soluble
protein, cytokinin and ethylene, auxin and lower levels of IAA oxidase activity and
gibberellic acid (Manjarekar et al., 2018, Rajatiya et al., 2018 and Saheda et al., 2019).
The ability of cultivars to bear fruit set also depends upon the availability of pollen, its
viability, population of pollinating insects and self and cross-compatibility of a cultivar,
abortion of embryo, low stigmatic receptivity, lack of irrigation and competition between
developing fruitlets. Along with these abiotic factors, the incidence of powdery mildew,
anthracnose disease, and hoppers can cause flower and fruit drops. The temperature was
found to play a superior role in fruit set, low, as well as high temperatures, affect the fruit set
in mango. Mallika hybrid of 20 years of aged trees (3.4 %) with a spray of plant protection
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Climate resilient agriculture for risk mitigation