scholarly journals Pollinator Maintenance vs. Fruit Production: Partitioned Reproductive Effort in Subdioecious Fuchsia Lycioides

1982 ◽  
Vol 69 (1) ◽  
pp. 199 ◽  
Author(s):  
Peter R. Atsatt ◽  
Philip W. Rundel
2020 ◽  
Vol 11 ◽  
Author(s):  
Lilong Wang ◽  
Yulin Li ◽  
Yulong Duan ◽  
Jie Lian ◽  
Yongqing Luo ◽  
...  

Caragana microphylla is a sand-fixing leguminous shrub with strong resistance to drought, cold, and low soil fertility. As a result, it plays an essential role in combating desertification in northern China, but little is known about its nutrient budget. Nutrient resorption is a key process in plant nutrient conservation and has marked ecological implications for plant fitness and ecosystem nutrient cycling. We studied the effects of both nitrogen (N) addition and reproductive effort on leaf N resorption of C. microphylla in a temperate semi-arid sandy land in China. The results showed that sprouting of the early leaves from over-wintered buds employs a strategy for slow returns on nutrient investment with smaller specific leaf area (SLA) and higher N resorption efficiency, whereas the late leaves, which sprout from current-year buds, employ a strategy for quick returns on nutrient investment with higher SLA and lower N resorption efficiency. N addition significantly increased the N resorption efficiency from early leaves while exerting no impact on late leaves, suggesting that the increased N recovery from early leaves is done to sustain the high N demands of late leaves. Reproductive effort did not affect the N resorption from early or late leaves due to the temporal separation between fruit production and leaf senescence. Taken together, our results demonstrate that C. microphylla has evolved different investment strategies for leaf N in early and late leaves to conserve nutrients and facilitate its growth in desertified environments.


2009 ◽  
Vol 18 (5) ◽  
pp. 623 ◽  
Author(s):  
Mark Borchert ◽  
Claudia M. Tyler

For many geophytes living in Mediterranean ecosystems, the passage of fire can produce bursts of flowering, seed production, vegetative growth, and seedling recruitment. In the present study, we investigated patterns of flowering and fruit production of the chaparral geophyte Chlorogalum pomeridianum (common soap plant) at two sites: one burned in a prescribed fire and one in nearby unburned chaparral. Both sites burned in a wildfire 2 years later, and we continued monitoring marked plants for an additional 6 years, enabling us to observe the effects of recent reburning on reproduction and growth. We found that flowering was stimulated by fire but was not strictly fire-dependent. There was a positive relationship between bulb size and leaf area, as well as between these two characteristics and flower and fruit production. Flower stalk initiation occurred when plants reached a minimum leaf area of ~1000 cm2, indicating that a minimum bulb size must be reached before reproductive effort is initiated. Direct herbivory of flowering stalks reduced fruiting and leaf herbivory indirectly prevented the initiation of flowering stalks. In the first several years after fire, flower and fruit production could be explained by resource matching but in subsequent years, resource matching was replaced by resource switching.


AoB Plants ◽  
2020 ◽  
Vol 12 (4) ◽  
Author(s):  
Elizabeth A Sinclair ◽  
Jane M Edgeloe ◽  
Janet M Anthony ◽  
John Statton ◽  
Martin F Breed ◽  
...  

Abstract Populations at the edges of their geographical range tend to have lower genetic diversity, smaller effective population sizes and limited connectivity relative to centre of range populations. Range edge populations are also likely to be better adapted to more extreme conditions for future survival and resilience in warming environments. However, they may also be most at risk of extinction from changing climate. We compare reproductive and genetic data of the temperate seagrass, Posidonia australis on the west coast of Australia. Measures of reproductive effort (flowering and fruit production and seed to ovule ratios) and estimates of genetic diversity and mating patterns (nuclear microsatellite DNA loci) were used to assess sexual reproduction in northern range edge (low latitude, elevated salinities, Shark Bay World Heritage Site) and centre of range (mid-latitude, oceanic salinity, Perth metropolitan waters) meadows in Western Australia. Flower and fruit production were highly variable among meadows and there was no significant relationship between seed to ovule ratio and clonal diversity. However, Shark Bay meadows were two orders of magnitude less fecund than those in Perth metropolitan waters. Shark Bay meadows were characterized by significantly lower levels of genetic diversity and a mixed mating system relative to meadows in Perth metropolitan waters, which had high genetic diversity and a completely outcrossed mating system. The combination of reproductive and genetic data showed overall lower sexual productivity in Shark Bay meadows relative to Perth metropolitan waters. The mixed mating system is likely driven by a combination of local environmental conditions and pollen limitation. These results indicate that seagrass restoration in Shark Bay may benefit from sourcing plant material from multiple reproductive meadows to increase outcrossed pollen availability and seed production for natural recruitment.


1991 ◽  
Vol 7 (2) ◽  
pp. 243-256 ◽  
Author(s):  
P. Charles-Dominique

ABSTRACTThe frugivorous phyllostomid bat Carollia perspicillata is closely associated with specific fruits which are found and picked in flight, then eaten at a feeding roost. Each fruit eaten corresponds to a single flight. An apparatus designed for this study permits the simultancous tracking of 10 bats equipped with double rhythm transmitters (slow rate corresponding to resting position and rapid rate to flying bouts). (1) The number of flights, (2) the percentage time spent flying and (3) the range of activity were recorded for different categories of animals during two periods of fruit production. Heavier males displayed high activity, while other males, non-breeding females and females in early pregnancy displayed a similar pattern of flying behaviour. Full-term pregnant females and lactating females performed almost as many flying bouts as non-reproductive females, but these flights were much shorter. This unexpected feeding strategy can be interpreted as a means of shifting energy to reproductive effort from exploratory behaviour (non-breeding females performed longer flights which combine the survey of environment and the fruit collection). This strategy, based upon the optimization of flying bouts, is in contrast to those of non-flying mammals and probably is only compatible with periods of high food production.


2018 ◽  
Vol 5 (2) ◽  
pp. 60-67 ◽  
Author(s):  
Dwi Yulianto ◽  
Retno Nugroho Whidhiasih ◽  
Maimunah Maimunah

ABSTRACT   Banana fruit is a commodity that contributes a great value to both national and international fruit production achievement. The government through the National Standardization Agency establishes standards to maintain the quality of bananas. The purpose of this Project is to classify the stages of maturity of Ambon banana base on the color index using Naïve Bayes method in accordance with the regulations of SNI 7422:2009. Naive Bayes is used as a method in the classification process by comparing the probability values generated from the variable value of each model to determine the stage of Ambon banana maturity. The data used is the primary data image of 105 pieces of Ambon banana. By using 3 models which consists of different variables obtained the same greatest average accuracy by using the 2nd model which has 9 variable values (r, g, b, v, * a, * b, entropy, energy, and homogeneity) and the 3rd model has 7 variable values (r, g, b, v , * a, entropy and homogeneity) that is 90.48%.   Keywords: banana maturity, classification, image processing     ABSTRAK   Buah pisang merupakan komoditas yang memberikan kontribusi besar terhadap angka produksi buah nasional maupun internasional. Pemerintah melalui Badan Standarisasi Nasional menetapkan standar untuk buah pisang, menjaga mutu  buah pisang. Tujuan dari penelitian ini adalah klasifikasi tahapan kematangan dari buah pisang ambon berdasarkan indeks warna menggunakan metode Naïve Bayes  sesuai dengan SNI 7422:2009. Naive bayes digunakan sebagai metode dalam proses pengklasifikasian dengan cara membandingkan nilai probabilitas yang dihasilkan dari nilai variabel penduga setiap model untuk menentukan tahap kematangan pisang ambon. Data yang digunakan adalah data primer citra pisang ambon sebanyak 105. Dengan menggunakan 3 buah model yang terdiri dari variabel penduga yang berbeda didapatkan akurasi rata-rata terbesar yang sama yaitu dengan menggunakan model ke-2 yang mempunyai 9 nilai variabel (r, g, b, v, *a, *b, entropi, energi, dan homogenitas) dan model ke-3 yang mempunyai 7 nilai variabel (r, g, b, v, *a, entropi dan homogenitas) yaitu sebesar 90.48%.   Kata Kunci : kematangan pisang,  klasifikasi, pengolahan citra


2015 ◽  
Vol 63 (2) ◽  
pp. 198-212 ◽  
Author(s):  
Jerzy Szwagrzyk ◽  
Georg Gratzer ◽  
Hanna Stępniewska ◽  
Janusz Szewczyk ◽  
Bojana Veselinovic

2020 ◽  
Vol 105 (3) ◽  
pp. 281-299
Author(s):  
Javier Carreño-Barrera ◽  
Luis Alberto Núñez-Avellaneda ◽  
Maria José Sanín ◽  
Artur Campos D. Maia

Solitary, dioecious, and mostly endemic to Andean cloud forests, wax palms (Ceroxylon Bonpl. ex DC. spp.) are currently under worrisome conservation status. The establishment of management plans for their dwindling populations rely on detailed biological data, including their reproductive ecology. As in the case of numerous other Neotropical palm taxa, small beetles are assumed to be selective pollinators of wax palms, but their identity and relevance in successful fruit yield were unknown. During three consecutive reproductive seasons we collected data on population phenology and reproductive and floral biology of three syntopic species of wax palms native to the Colombian Andes. We also determined the composition of the associated flower-visiting entomofauna, quantifying the extent of the role of individual species as effective pollinators through standardized value indexes that take into consideration abundance, constancy, and pollen transport efficiency. The studied populations of C. parvifrons (Engel) H. Wendl., C. ventricosum Burret, and C. vogelianum (Engel) H. Wendl. exhibit seasonal reproductive cycles with marked temporal patterns of flower and fruit production. The composition of the associated flower-visiting entomofauna, comprised by ca. 50 morphotypes, was constant across flowering seasons and differed only marginally among species. Nonetheless, a fraction of the insect species associated with pistillate inflorescences actually carried pollen, and calculated pollinator importance indexes demonstrated that one insect species alone, Mystrops rotundula Sharp, accounted for 94%–99% of the effective pollination services for all three species of wax palms. The sequential asynchronous flowering of C. parvifrons, C. ventricosum, and C. vogelianum provides an abundant and constant supply of pollen, pivotal for the maintenance of large populations of their shared pollinators, a cooperative strategy proven effective by high fruit yield rates (up to 79%). Reproductive success might be compromised for all species by the population decline of one of them, as it would tamper with the temporal orchestration of pollen offer.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 498e-498
Author(s):  
S. Paramasivam ◽  
A.K. Alva

For perennial crop production conditions, major portion of nutrient removal from the soil-tree system is that in harvested fruits. Nitrogen in the fruits was calculated for 22-year-old `Hamlin' orange (Citrus sinensis) trees on Cleopatra mandarin (Citrus reticulata) rootstock, grown in a Tavares fine sand (hyperthermic, uncoated, Typic Quartzipsamments) that received various N rates (112, 168, 224, and 280 kg N/ha per year) as either i) broadcast of dry granular form (DGF; four applications/year), or ii) fertigation (FRT; 15 applications/year). Total N in the fruits (mean across 4 years) varied from 82 to 110 and 89 to 111 kg N/ha per year for the DGF and FRT sources, respectively. Proportion of N in the fruits in relation to N applied decreased from 74% to 39% for the DGF and from 80% to 40% for the FRT treatments. High percentage of N removal in the fruits in relation to total N applied at low N rates indicate that trees may be depleting the tree reserve for maintaining fruit production. This was evident, to some extent, by the low leaf N concentration at the low N treatments. Furthermore, canopy density was also lower in the low N trees compared to those that received higher N rates.


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