scholarly journals Cross-pollination Enhances Macadamia Yields, Even With Branch-level Resource Limitation

HortScience ◽  
2019 ◽  
Vol 54 (4) ◽  
pp. 609-615 ◽  
Author(s):  
Brad G. Howlett ◽  
Samantha F.J. Read ◽  
Maryam Alavi ◽  
Brian T. Cutting ◽  
Warrick R. Nelson ◽  
...  
Keyword(s):  
Resource Allocation ◽  
Strong Evidence ◽  
High Intensity ◽  
Resource Limitation ◽  
Yield Potential ◽  
Cross Pollination ◽  
Self Pollination ◽  
Lack Of Information ◽  
Pollination Deficit

Macadamia is partially self-incompatible and cross-pollination is considered important to improve yields. However, questions remain regarding the importance of self- vs. cross-pollination, and subsequently whether managed pollinators are useful in commercial orchards. Pollinators play a key role in cross-pollination, but for self-pollination, the protandrous florets might also benefit from the movement of potentially more viable self-pollen among florets, racemes, and trees through pollinator movement. There is also a lack of information on pollination deficits throughout orchards and whether by increasing the intensity of cross-pollination, final nut yield is limited by within-tree resource allocation. Using caged and bagged racemes on three cultivars, we found strong evidence for self-pollination, but no evidence that hand moving self-pollen within racemes, between racemes, or between trees improved final nut set. In all cases, hand cross-pollinated racemes yielded significantly more nuts. Hand cross-pollinated racemes also produced significantly more developed nuts than open-pollinated racemes (all racemes were exposed to pollinators). However, by increasing the intensity of hand cross-pollination per tree, we showed that resource allocation probably overinflates these measures of pollination deficit in macadamia. Despite this, our findings point to an opportunity to increase yields through additional cross-pollination, as high-intensity hand cross-pollination of flowering racemes within trees still resulted in increased nut set. Although self-pollination can occur in macadamia, to optimize yield potential, strategies to maximize cross-pollination should be adopted.

scholarly journals Pollination Strategies to Improve Fruit Set in Orchards of ‘Manzanilloʼ Olive in a Nontraditional Producing Country, Mexico

2019 ◽  
Vol 29 (3) ◽  
pp. 258-264 ◽  
Author(s):  
Alberto Sánchez-Estrada ◽  
Julián Cuevas
Keyword(s):  
Fruit Set ◽  
Fruit Weight ◽  
Open Pollination ◽  
Positive Effects ◽  
Cross Pollination ◽  
Self Pollination ◽  
Pollination Deficit ◽  
Olive Trees ◽  
Compatible Pollen ◽  
The Right

In countries new to producing ‘Manzanillo’ olive trees (Olea europaea), free cross-pollination is often insufficient to obtain high levels of fruit set. An appropriate pollination design is therefore essential to ensure a timely, abundant, and compatible pollen supply. With a view to determining whether a pollination deficit exists in a nontraditional olive area such as the northern Mexico, pollination experiments were carried out in two consecutive seasons in both a monovarietal and a multivarietal Manzanillo orchard, where Sevillano, Barouni, Picual, Pendolino, Mission, Nevadillo, and Frantoio trees were growing nearby. The pollination treatments were self-, open, and cross-pollination with ‘Barouni’ and ‘Sevillano’ pollen, the latter only in the multivarietal orchard. The results confirmed the full self-incompatible condition of ‘Manzanillo’. Open-pollination did not improve fruit set in the monovarietal orchard, but it did so significantly in the multivarietal plot, where fruit set levels under open-pollination matched those of cross-pollination. Lower pollen adhesion, as well as occasional decreased germination, and reduced and delayed pollen tube growth were observed under self-pollination, highlighting self-incompatibility reactions. The reduction in fertilization rates led to low fruit set under self-pollination. Positive effects of open- and cross-pollination treatments were also noted on fruit weight (despite higher crop loads) and pulp-to-pit ratios. A strategic plantation design, including appropriate pollinizers in the right number and position, is therefore suggested for increasing ‘Manzanillo’ fruit quality and yield in Mexico. Both ‘Barouni’ and ‘Sevillano’ served as efficient pollinizers for ‘Manzanillo’, although we recommend ‘Barouni’ as a more efficient because the bloom periods of them matched that of ‘Manzanillo’

scholarly journals Cytological Observation and Transcriptome Comparative Analysis of Self-Pollination and Cross-Pollination in Dendrobium Officinale

Genes ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 432
Author(s):  
Yaling Chen ◽  
Benchang Hu ◽  
Fantao Zhang ◽  
Xiangdong Luo ◽  
Jiankun Xie
Keyword(s):  
Pollen Tubes ◽  
The Self ◽  
Dendrobium Officinale ◽  
Self Incompatibility ◽  
Related Gene ◽  
Cytological Observation ◽  
Lectin Receptor ◽  
Cross Pollination ◽  
Self Pollination ◽  
Medicinal Value

Dendrobium officinale is a rare and traditional medicinal plant with high pharmacological and nutritional value. The self-incompatibility mechanism of D. officinale reproductive isolation was formed in the long-term evolution process, but intraspecific hybridization of different germplasm resources leads to a large gap in the yield, quality, and medicinal value of D. officinale. To investigate the biological mechanism of self-incompatibility in D. officinale, cytological observation and the transcriptome analysis was carried out on the samples of self-pollination and cross-pollination in D. officinale. Results for self-pollination showed that the pollen tubes could grow in the style at 2 h, but most of pollen tubes stopped growing at 4 h, while a large number of cross-pollinated pollen tubes grew along the placental space to the base of ovary, indicating that the self-incompatibility of D. officinale may be gametophyte self-incompatibility. A total of 63.41 G basesum of D. officinale style samples from non-pollinated, self-pollination, and cross-pollination by RNA-seq were obtained, and a total of 1944, 1758, and 475 differentially expressed genes (DEGs) in the comparison of CK (non-pollinated) vs. HF (cross-pollination sample), CK vs. SF (self-pollination sample) and SF vs. HF were identified, respectively. Forty-one candidate genes related to self-incompatibility were found by function annotation of DEGs, including 6 Ca2+ signal genes, 4 armed repeat containing (ARC) related genes, 11 S-locus receptor kinase (SRK) related genes, 2 Exo70 family genes, 9 ubiquitin related genes, 1 fatty acid related gene, 6 amino acid-related genes, 1 pollen-specific leucine-rich repeat extensin-like protein (LRX) related gene and 1 lectin receptor-like kinases (RLKs) related gene, showed that self-incompatibility mechanism of D. officinale involves the interaction of multiple genes and pathways. The results can provide a basis for the study of the self-incompatibility mechanism of D. officinale, and provide ideas for the preservation and utilization of high-quality resources of D. officinale.

scholarly journals Time of flowering and fertilisation of quince varieties

1999 ◽  
Vol 5 (1-2) ◽  
Author(s):  
T. Szabó ◽  
J. Nyéki ◽  
M. Soltész ◽  
Z. Szabó ◽  
T. Tóth
Keyword(s):  
Fruit Set ◽  
Fruit Size ◽  
Late Flowering ◽  
Cross Pollination ◽  
Self Pollination ◽  
The Individual ◽  
Contradictory Data

Literature dealing with flowering and fertilisation of quince is scarce. Most controversial and scanty are informations on observations of self- and cross-pollination. According to our observations, differences in blooming time are few (2-3) days only, thus flowering of most varieties is synchronous. The varieties observed are grouped as early, intermediate and late flowering ones. Self fertility of the individual varieties, however, was not assessed unequivocally, therefore it is recommended, by safety reasons, to consider quince actually as a whole to be auto-incompatible. Artificial self-pollination (or rather geitonogamy) as well as cross pollination with other varieties increased substantially fruit set if compared with the results of natural self-pollination (autogamy). According to the fruit set of their open pollinated flowers, varieties have been classified according to fertility as low (below 10 %), medium (between 10 and 20 %) and high (more than 20 %). Cross fertility of varieties is highly variable depending on combination and on season. Contradictory data are probably due to the sensitivity of quince to conditions of search. Better fruit set was coincident with higher number of stout seeds per fruit. Well developed seeds are definitely a prerequisite of larger fruit size.  

Seed abortion in the bat pollinated Neotropical tree species, Caryocar brasiliense (Caryocaraceae)

Botany ◽  
2009 ◽  
Vol 87 (11) ◽  
pp. 1110-1115 ◽  
Author(s):  
Rosane G. Collevatti ◽  
Raquel Estolano ◽  
Silmara F. Garcia ◽  
John D. Hay
Keyword(s):  
Inbreeding Depression ◽  
Tree Species ◽  
Resource Limitation ◽  
Sibling Rivalry ◽  
Assignment Test ◽  
Seed Abortion ◽  
Neotropical Tree ◽  
Self Pollination ◽  
Caryocar Brasiliense ◽  
Maternal Regulation

In self-compatible plants, the reduction in brood size may be caused either by inbreeding depression, resource limitation, maternal regulation of offspring quality, or by sibling rivalry. We studied seed abortion in Caryocar brasiliense Camb. (Caryocaraceae), a Neotropical tree species, to verify whether seeds sired by self-pollination are aborted. Fruits were sampled from 23 mother trees to estimate seed set and proportion of aborted seeds. Ripened and aborted seeds from 18 mother trees were genotyped using 10 microsatellite loci together with mother trees and all nearby adults (83 adults) to determine the pollen donor by assignment test. From the 541 seeds, 190 were aborted and the mean number of aborted seeds per fruit was 0.627 (SD = 0.807). Proportion of aborted seeds was different among mother trees and among fruits within mother trees. All but three aborted seeds were sired by self-pollination and selfed seeds were aborted in fruits harbouring both selfed and outcrossed seeds. Aborted outcrossed seeds were sired by pollen donors closely related to mother trees. Our results strongly support that seed abortion in C. brasiliense may be the outcome of inbreeding depression and sibling rivalry when selfed and outcross pollinated ovules compete.

The mating system of Acrotriche serrulata (Ericaceae)

2010 ◽  
Vol 58 (2) ◽  
pp. 124 ◽  
Author(s):  
Melanie Schneemilch ◽  
Emma Steggles
Keyword(s):  
Mating System ◽  
Pollen Viability ◽  
Seed Viability ◽  
Corolla Tube ◽  
Morphological Features ◽  
Stigma Receptivity ◽  
Pollination Experiments ◽  
Controlled Pollination ◽  
Cross Pollination ◽  
Self Pollination

Controlled pollination experiments were conducted on Acrotriche serrulata R.Br. (Ericaceae) to determine the mating system for this species. Pollen viability and stigma receptivity were investigated to ensure effective timing and sourcing of material for maximum fertilisation. Stigmas were found to be receptive in mature buds, with receptivity maintained while nectar remained within the corolla tube. Germination testing showed that pollen from within mature buds was viable. The mating system of A. serrulata was found to be predominantly outcrossing, with 49.8% of cross-pollinated flowers developing to fruit, compared with 8.7% of self-pollinated flowers. Seed viability did not differ significantly between fruits produced by cross-pollination and those produced by self-pollination, although this may be attributable to low sample sizes available for self-pollinated fruits. These results in combination with morphological features of the flower suggest that a pollinator is required for this species.

Breeding System and Tests for Pollen-Limitation in Two Species of Banksia

1990 ◽  
Vol 38 (1) ◽  
pp. 63 ◽  
Author(s):  
RL Goldingay ◽  
RJ Whelan
Keyword(s):  
Breeding System ◽  
Reproductive Output ◽  
Fruit Set ◽  
Pollen Limitation ◽  
Floral Display ◽  
Cross Pollination ◽  
Self Pollination

Three factors that potentially influence fruit set (breeding system, inadequate cross-pollination and variable floral display) were examined for two species of Banksia. Firstly, self-pollination and autogamy treatments failed to produce any fruit in B. spinulosa and produced very few fruit in B. paludosa. This suggests that cross pollen is required to produce the level of fruit set observed in the field. Secondly, when plants were given abundant cross pollen, fruit set was not altered in B. spinulosa but was in B. paludosa. Although the number of follicles per inflorescence was was not different for open- pollinated (control) and manipulated B. paludosa inflorescences, the latter produced twice the proportion of inflorescences with follicles produced by control plants and twice the total number of follicles per plant. Thirdly, larger floral display in open-pollinated B. spinulosa plants was associated with a greater production of fruit. However, larger floral display was not associated with a greater reproductive output in B. paludosa, and we suggest that recurrent pollen-limitation in this species may be responsible for this result.

scholarly journals Construction of a male sterility system for hybrid rice breeding and seed production using a nuclear male sterility gene

2016 ◽  
Vol 113 (49) ◽  
pp. 14145-14150 ◽  
Author(s):  
Zhenyi Chang ◽  
Zhufeng Chen ◽  
Na Wang ◽  
Gang Xie ◽  
Jiawei Lu ◽  
...  
Keyword(s):  
Male Sterility ◽  
Seed Production ◽  
Environmental Conditions ◽  
Hybrid Rice ◽  
Rice Breeding ◽  
Male Sterile ◽  
Red Fluorescence ◽  
Cytoplasmic Male Sterile ◽  
Cross Pollination ◽  
Self Pollination

The breeding and large-scale adoption of hybrid seeds is an important achievement in agriculture. Rice hybrid seed production uses cytoplasmic male sterile lines or photoperiod/thermo-sensitive genic male sterile lines (PTGMS) as female parent. Cytoplasmic male sterile lines are propagated via cross-pollination by corresponding maintainer lines, whereas PTGMS lines are propagated via self-pollination under environmental conditions restoring male fertility. Despite huge successes, both systems have their intrinsic drawbacks. Here, we constructed a rice male sterility system using a nuclear gene named Oryza sativa No Pollen 1 (OsNP1). OsNP1 encodes a putative glucose–methanol–choline oxidoreductase regulating tapetum degeneration and pollen exine formation; it is specifically expressed in the tapetum and miscrospores. The osnp1 mutant plant displays normal vegetative growth but complete male sterility insensitive to environmental conditions. OsNP1 was coupled with an α-amylase gene to devitalize transgenic pollen and the red fluorescence protein (DsRed) gene to mark transgenic seed and transformed into the osnp1 mutant. Self-pollination of the transgenic plant carrying a single hemizygous transgene produced nontransgenic male sterile and transgenic fertile seeds in 1:1 ratio that can be sorted out based on the red fluorescence coded by DsRed. Cross-pollination of the fertile transgenic plants to the nontransgenic male sterile plants propagated the male sterile seeds of high purity. The male sterile line was crossed with ∼1,200 individual rice germplasms available. Approximately 85% of the F1s outperformed their parents in per plant yield, and 10% out-yielded the best local cultivars, indicating that the technology is promising in hybrid rice breeding and production.

scholarly journals Preliminary evaluation of pollen quality, fertility relations and fruit set of selected sour cherry cultivars in polish conditions

2012 ◽  
Vol 61 (1) ◽  
pp. 71-77 ◽  
Author(s):  
Ewa Szpadzik ◽  
Ewa Jadczuk-Tobjasz ◽  
Barbara Łotocka
Keyword(s):  
Fruit Set ◽  
Sour Cherry ◽  
Preliminary Evaluation ◽  
Open Pollination ◽  
Pollen Quality ◽  
Cross Pollination ◽  
Self Pollination

Preliminary experiments were carried out in spring 2006. The percentage of fruit set of 'Schattenmorelle IR-2', 'Koral', 'Debreceni Bötermö', 'újfefértói Fürtos' and 'Karneol' was higher after open pollination compared with self-pollination. The cultivar Vowi had an inconsiderably higher percentage of fruit set after self-pollination compared with open pollination. The percentage of fruit set in 'Debreceni Bötermö' and 'újfehértói Fürtos' was about 25 % higher after pollination by 'Schattenmorelle IR-2' and 'Koral' compared with the percentage of fruit set after cross - pollination of both cultivars with each other. In general, they did not appear to be good pollinators with each other. The highest quality of pollen was observed for the following cultivars: 'Schattenmorelle IR-2', 'Koral' and Vowi and the lowest result was obtained in 'újfehértói Fürtos'. The highest yield was given by the following cultivars: Vowi, Schattenmorelle IR-2 and Koral.

scholarly journals Flower visitors of Streptocarpus teitensis: implications for conservation of a critically endangered African violet species in Kenya

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e10473
Author(s):  
Mark Otieno ◽  
Neelendra Joshi ◽  
Benjamin Rutschmann
Keyword(s):  
Breeding System ◽  
Fruit Set ◽  
Safety Net ◽  
Critically Endangered ◽  
Flower Visitors ◽  
Critically Endangered Species ◽  
African Violet ◽  
Cross Pollination ◽  
Self Pollination ◽  
Published Evidence

Background The African violets are endangered plant species restricted mainly to the Eastern Arc Mountains biodiversity hotspots in Kenya and Tanzania. These plants grow well in shaded environments with high humidity. Given their restricted geographical range and published evidence of dependance on insect vectors to facilitate sexual reproduction, understanding their pollination biology is vital for their survival. Methods We conducted an empirical study using flower visitor observations, pan trapping and bagging experiments to establish the role of flower visitors in the fruit set of a locally endemic and critically endangered species of African violet in Taita Hills, Kenya, Streptocarpus teitensis. Results The study found that fruit set is increased by 47.8% in S. teitensis when flowers are visited by insects. However, it is important to note the presence of putative autogamy suggesting S. teitensis could have a mixed breeding system involving self-pollination and cross-pollination since bagged flowers produced 26.9% fruit set. Conclusions Insects appear to be essential flower visitors necessary for increased fruit set in S. teitensis. However, there is evidence of a mixed breeding system involving putative self-pollination and cross-pollination suggesting that S. teitensis is somewhat shielded from the negative effects of pollinator losses. Consequently, S. teitensis appears to be protected to a degree from the risks such as reproduction failure associated with pollinator losses by the presence of a safety net in putative self-pollination.

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