Viability of pollen grains and stigma receptivity in Desert Rose

Abstract

Adenium obesum (Forssk.) Roem. & Schult., popularly known as desert rose, has become a valuable ornamental plant. In floriculture, the production of hybrids is prioritized. Hence, knowledge on floral biology and sexual reproduction of the target species is fundamental. The objectives of this study were: (1) to test sucrose concentrations and temperatures for in vitro germination of A. obesum pollen grains; (2) to identify the effect of temperature on the viability of A. obesum pollen grains; and (3) to evaluate the viability of pollen grains and stigma receptivity in pre-anthesis, at flower opening, and 72 h post-flower opening in three accessions of A. obesum. A significant relationship between temperatures and sucrose concentrations was observed in the in vitro germination test. The highest percentage of in vitro germination of pollen grains, 39.81%, was observed at an estimated temperature of 26.05 °C. Desert rose accessions maintained in biochemical oxygen demand (BOD) chambers at 30 °C during a 16-h light photoperiod showed faster flowering, and temperatures ≥ 25 °C induced pollen grain viability percentages above 69%. Temperature is one of the most important abiotic factors, influencing mainly in pollen germination, pollen tube growing and in efficiency fertilization. The ICA-wd accession stood out and can be considered a pollen donor in artificial pollination. The stigmas of flowers were receptive from a day before flower opening until three days after. The two parameters presented above, stigma receptivity and pollen viability, allow inferences about the appropriate time for successful pollination and subsequent fertilization in desert roses.

Zinc Nutrition Responses to Agronomic and Yield Traits, Kernel Quality, and Pollen Viability in Rice (Oryza sativa L.)

“…The recent results are in agreement with this finding which stated that the pollen morphology has become an essential descriptor (Lechowicz et al, 2020 ; Souza et al, 2022 ), and the pollen grains have their own unique set of attributes such as the size, exine structure, and pore size (Evrenosoglu and Misirli, 2009 ). This study considers a helpful tool to monitor the impact of Zn fertilizers on pollen grain viability test for understanding the viability and capacity of pollen grain which is vital for the reproductive biology and genetic breeding of plants, and this is in agreement with the study of Dane and Lang ( 2004 ) and Gomaa et al ( 2021 ).…”

Como a assimetria de seleção e de especialização afetam a dinâmica coevolutiva em mutualismos?

“…Therefore, pollen smothering may compose the total pollen in the pollinator and increase the chance of dispersion to the next individual from the youngest flowers and pollen grains, which can be more viable (Souza et al, 2022). In this way, pollen smothering would promote gamete inundation on the stigmatic surface, by a higher deposition of pollen, as we show in our results.…”

Different storage temperatures and times on pollen quality in cut rose varieties

“…However, several problems such as a decline in fruit and seed set affect crossbreeding success. To avoid these problems, rose breeders must choose genotypes having high pollen viability and germination rate as a pollen parent (Souza et al, 2022). They must determine the pollen viability and germination rate of the genotype used as a parent because pollen viability and germination rate show variation in genotypes and environmental conditions (Giovannini et al, 2017;Pacini and Dolferus, 2019).…”

“…Many researches have been carried out to determine pollen viability and germination rates and to reveal the duration of pollen viability (Zlesak et al, 2007;Aldahadha et al, 2020;Iovane et al, 2022;Souza et al, 2022). In these researches, it was determined that the duration of keeping the viability of pollen differs depending on the conditions in which they are kept and the species and variety used (Rathod et al, 2018;Bheemanahalli et al, 2021;Ravindra et al, 2022;Souza et al, 2022).…”

“…Many researches have been carried out to determine pollen viability and germination rates and to reveal the duration of pollen viability (Zlesak et al, 2007;Aldahadha et al, 2020;Iovane et al, 2022;Souza et al, 2022). In these researches, it was determined that the duration of keeping the viability of pollen differs depending on the conditions in which they are kept and the species and variety used (Rathod et al, 2018;Bheemanahalli et al, 2021;Ravindra et al, 2022;Souza et al, 2022). Temperature is one of the most important conditions affecting the viability and longevity of pollen life, and it has been reported that keeping many species and varieties of pollen at low temperatures such as -80 ºC, -20 ºC, 0 ºC, 4 ºC for certain periods provides successful results (Zlesak et al, 2007;Du et al, 2019;Aldahadha et al, 2020).…”