Discrimination of intra- and inter-specific forage quality by collared pikas (Ochotona collaris)

2008 ◽  
Vol 86 (6) ◽  
pp. 456-461 ◽  
Author(s):  
S. F. Morrison ◽  
D. S. Hik

The specific nutritional characteristics by which herbivores evaluate their foraging options are complex. We experimentally manipulated the crude protein and water content of two forage species ( Carex consimilis Holm. (= Carex bigelowii Torr. ex Schwein.) and Polygonum bistorta L.) commonly cached by collared pikas ( Ochotona collaris (Nelson, 1893)) to determine their influence on inter- and intra-specific forage selection. Preference data were collected for 27 pikas using cafeteria-style feeding trials in a randomized block design. A three-way interaction (species × protein × water) suggested that pikas made conditional forage selection decisions while caching these plants. The interaction was driven by greater selection for fresh rather than dried C. consimilis when both were not fertilized. Water content had no effect on the selection of either fertilized C. consimilis or fertilized P. bistorta. Overall, our results indicate that pikas made subtle decisions about their selection of vegetation during caching, based on variation in nitrogen and water content in addition to species-specific selection criteria. Further, our results imply that tests of foraging theory may need to consider intra-specific variation in forage characteristics, as well as inter-specific ranking of forage species.

REVISTA FIMCA ◽  
2018 ◽  
Vol 5 (2) ◽  
pp. 28-31
Author(s):  
Darlan Darlan Sanches Barbosa Alves ◽  
Victor Mouzinho Spinelli ◽  
Marcos Santana Moraes ◽  
Carolina Augusto De Souza ◽  
Rodrigo da Silva Ribeiro ◽  
...  

Introdução: O estado de Rondônia se destaca como tradicional produtor de café, sendo o segundo maior produtor brasileiro de C. canephora. No melhoramento genético de C. canephora, a seleção de plantas de elevada peneira média está associada à bebida de qualidade superior. Objetivos: O objetivo desse estudo foi avaliar a variabilidade genética de clones de C. canephora para o tamanho dos grãos, mensurado a partir da avaliação da peneira média (PM). Materiais e Métodos: Para isso, foi conduzido ao longo de dois anos agrícolas experimento no campo experimental da Embrapa no município de Ouro Preto do Oeste-RO, para a avaliação da peneira média de 130 genótipos (clones) com características das variedades botânicas Conilon, Robusta e híbridos intervarietais. O delineamento experimental utilizado foi de blocos ao acaso, com quatro repetições de quatro plantas por parcela. Resultados: Não houve resultados significativos para a interação clones X anos, indicando uma maior consistência no comportamento das plantas ao longo do tempo. Porém foram observadas diferenças significativas para o tamanho dos grãos entre os genótipos avaliados, possibilitando selecionar genótipos superiores. Conclusão: Os genótipos agruparam-se em cinco classes de acordo com o teste de média, subsidiando a caracterização de um gradiente de variabilidade da característica avaliada ABSTRACTIntroduction: Coffea canephora accounts for approximately 35% of the world's coffee production. The state of Rondônia stands out as a traditional coffee producer, being the second largest Brazilian producer of C. canephora. In the classical genetic improvement of C. anephora, the selection of plants of high average sieve is associated with a drink of superior quality. Objectives: The objective of this udy was to evaluate the genetic variability of Coffea canephora clones for the agronomic medium sieve (PM). Materials and Methods: The experiment was conducted in the experimental field of Embrapa, municipality of OuroPreto do Oeste-RO, located at coordinates 10º44'53 "S and 62º12'57". One hundred thirty genotypes (clones) of botanical characteristics Conilon, Robusta and intervarietal hybrids were evaluated in the agricultural years 2013-2014 and 2014-2015. The experimental design was a randomized block design with four blocks and four plants per plot, spacing 3.5 x 1.5 meters between plants. Results: Significant difference was found for the grain size. According to the F test, at 5% probability, the genotypes were grouped into five classes according to the mean test. Conclusion: The results obtained subsidized the characterization of a variability gradient of the evaluated trait.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 512e-512
Author(s):  
A.M. Shirazi

Six different Japanese Maples (Acer palmatum) cultivars `Water Fall', `Burgundy Lace', `Crimson Queen', `Oshio-Beni', `SangoKaKu', and `Bloodgood' from Monrovia Nursery were planted in a randomized block design on 4 June 1997 at the The Morton Arboretum. Leaf heat tolerance was evaluated by measuring ion leakage of the leaf tissue at 25–60 °C in July, Aug., and Sept. 1997. The LT50 (the temperature at which 50% of the tissues were injured) of all the cultivars were higher in July (≈53 °C) and were lower in September (≈47 °C). Water content of the leaf tissues were higher in July compare to August and September and were not related to heat tolerance of most cultivars. Stem cold hardiness was performed by artificial freezing tests in Oct., Dec., and Feb. 1997/98. The Lowest Survival Temperature (LST) for the most hardy to least hardy cultivars in October and December were: `Burgundy Lace' (–15, –27 °C), `Bloodgood' (–18, –24 °C), `Oshio-Beni' (–15, –24 °C), `Crimson Queen' (–15, –18 °C), `Water Fall' (–9, –18 °C) and `SangoKaKu' (–9, –12 °C), respectively. Growth, dormancy development, spring budbreak and performance of these cultivars will be compared.


2017 ◽  
Vol 39 (2) ◽  
pp. 137
Author(s):  
Marielly Maria Almeida Moura ◽  
Daniel Ananias de Assis Pires ◽  
Renê Ferreira Costa ◽  
Daniella Cangussú Tolentino ◽  
João Paulo Sampaio Rigueira ◽  
...  

 This study aimed to evaluate the nutritional characteristics and quality of silages of five sorghum genotypes, namely: Volumax, AG2005E, Qualimax, BRS610 and AG2501. The study was conducted at the Experimental Farm Unimontes, in the municipality of Janaúba, state of Minas Gerais. The treatments were distributed in a randomized block design with four replicates. Data were tested by analysis of variance andmeans were compared by Scott-Knott test at a significance level of 5%. The pH values ranged from 3.93 and 4.10. Genotypes differed in all studied nutritional characteristics (p < 0.05). For the acid detergent fiber, differences were detected between the genotypes, AG2501 (35.66%), Volumax (34.89%), AG2005E (34.53%), Qualimax (32.39%) and BRS610 (33.60%). The high participation of lignin was verifiedin all genotypes except for Volumax (4.14%). All silages were within the recommended range 50-65% for in vitro dry matter digestibility and classified as having good quality, however only the AG2005E genotype met nitrogen requirements for microbial fermentation, with 7.06% crude protein. 


2013 ◽  
Vol 48 (4) ◽  
pp. 411-416 ◽  
Author(s):  
Cecília Khusala Verardi ◽  
Erivaldo José Scaloppi Junior ◽  
Guilherme Augusto Peres Silva ◽  
Lígia Regina Lima Gouvêa ◽  
Paulo de Souza Gonçalves

The objective of this work was to assess the genetic parameters and to estimate genetic gains in young rubber tree progenies. The experiments were carried out during three years, in a randomized block design, with six replicates and ten plants per plot, in three representative Hevea crop regions of the state of São Paulo, Brazil. Twenty-two progenies were evaluated, from three to five years old, for rubber yield and annual girth growth. Genetic gain was estimated with the multi-effect index (MEI). Selection by progenies means provided greater estimated genetic gain than selection based on individuals, since heritability values of progeny means were greater than the ones of individual heritability, for both evaluated variables, in all the assessment years. The selection of the three best progenies for rubber yield provided a selection gain of 1.28 g per plant. The genetic gains estimated with MEI using data from early assessments (from 3 to 5-year-old) were generally high for annual girth growth and rubber yield. The high genetic gains for annual girth growth in the first year of assessment indicate that progenies can be selected at the beginning of the breeding program. Population effective size was consistent with the three progenies selected, showing that they were not related and that the population genetic variability is ensured. Early selection with the genetic gains estimated by MEI can be made on rubber tree progenies.


2018 ◽  
Vol 48 (4) ◽  
Author(s):  
Leilane Nicolino Lamarão de Oliveira ◽  
Rodrigo Barros Rocha ◽  
Fábio Medeiros Ferreira ◽  
Victor Mouzinho Spinelli ◽  
André Rostand Ramalho ◽  
...  

ABSTRACT: The objective of this research was to quantify the genetic divergence of potential Coffea canephora parents, with the goal of developing progenies that associate the best traits of the Conilon and Robusta botanical varieties for hybrid vigor expression. Thus, 10 morphological and productive characteristics of 130 clones of Conilon and Robusta botanical varieties and their intervarietal hybrids were evaluated over 2 years. The experiment was conducted in a randomized block design with four replicates of four plants per plot. For selection of parents, the main component analysis was used to associate values with reference points obtained from the average of each botanical variety. The first two principal components allowed for the separation of the botanical varieties representing the variability contained in the original data with 76% for the first year and 69% for the second year. Although, the genotype × years interaction had significant effects, there were minor differences in the grouping from one year to the next, which is associated with the higher repeatability estimates observed in this study. It was observed that crosses with the 16-1-81I, 9-1-82L, and 13-1-61I parents of the botanical variety Robusta and the 167I, 890E, and 130I parents of the Conilon botanical variety presented greater potential for obtaining selection gains.


Author(s):  
Anjani Kumar ◽  
D. N. Singh ◽  
Krishna Prasad ◽  
Avinash Pandey

The present investigation was carried out with F2 plants from a cross between two parents i.e., BPT-5204 and IR-64Drt1. The selection of parents for crosses was made based on genotypes that were tolerant and susceptible to drought condition. BPT-5204 was drought susceptible and IR-64Drt1 was also tolerant to drought. In this experiment adequate amount of variability was detected for grain yield per plant and its components among 324 segregants evaluated under augmented randomized block design II in normal field condition. The analysis of variance for grain yield and its attributing characters among blocks, treatments, entries, checks and checks vs entries revealed presence of significant variation in the segregants studied. However, with respect to checks, non-significant differences were recorded for only L/B ratio. The results indicated that among 324 rice genotypes including checks, only 9 rice genotypes expressed higher yield compared to seven checks varieties under normal field condition. The segregants S-51, S-122, S-135, S-195, S-199, S-210, S-219, S-222, S-251 were top ranking genotypes with respect to all checks.


2013 ◽  
Vol 4 (4) ◽  
pp. 356-364
Author(s):  
Luziano Lopes Da Silva ◽  
Márcio Antônio Da Silveira ◽  
Rodrigo Ribeiro Fidelis ◽  
Rodrigo de Castro Tavares ◽  
Valéria Gomes Momenté ◽  
...  

The sweet potato (Ipomoea batatas (l.) Lam.) Lam) is a plant that produces tuberous root belonging to the family convolvulácea explored in practically all states of Brazil. The objective of this work was to select genotypes of the sweet potato as the efficiency of phosphorus use in cerrado soils with high and low availability of this nutrient. Were evaluated nine genotypes of sweet potato coming from the germplasm bank from the Federal University of the Tocantins, Brazil. The experimental design was in randomized block design with three replications being nine genotypes grown in two environments with low and high phosphorus availability, using doses of phosphorus fertilization from 20 and 120 kg ha-1 P2O5, applied at planting. To select genotypes suitable for environments proposed was used methodology for selection of the efficient use and response to phosphorus fertilization (efficiency and response). Genotype Amanda was classified as efficient and responsive, Barbara, Julia, Marcela and Carolina Vitoria as efficient, but not responsive and Livia, Duda, Ana Clara and Beatriz were classified as non-efficient, responsive but the absorption and utilization of phosphorus.


2018 ◽  
Vol 85 (0) ◽  
Author(s):  
Suzete Fernandes Lima ◽  
Leandro Spíndola Pereira ◽  
Gustavo Dorneles Sousa ◽  
Simonny Araújo Vasconcelo ◽  
Adriano Jakelaitis ◽  
...  

ABSTRACT: The use of herbicide underdoses allows minimizing the competition of grasses on annual crops, enabling simultaneous cultivation. In this context, the objective of this study was to investigate glyphosate underdoses on the suppression of the initial growth of three Panicum maximum cultivars aiming at the integrated cultivation, in addition to the effects of forage species on the incidence and development of weeds. Three field experiments were conducted. The experimental design was a randomized block design with four replications and eight treatments consisting of increasing glyphosate doses (0, 54, 108, 270, 378, 540, 756, and 1,080 g a.e. ha−1). An atrazine dose of 1,200 g a.i. ha−1 was added to each treatment. Plant phytotoxicity assessments were performed at 7, 14, 21, and 28 days after application. At 80 and 125 days after sowing, the assessments of total dry matter production, leaf dry matter, stem dry matter, and leaf to stem ratio were carried out, in addition to density and dry matter production of weed community. Glyphosate underdoses below 215, 65, and 90 g a.e. ha-1 have a potential to be investigated aiming at the management of P. maximum cv. Atlas, P. maximum cv. Mombasa, and P. maximum cv. Tanzania under intercropping. The three forage species are effective in suppressing weeds.


2019 ◽  
Vol 4 (2) ◽  
pp. 62
Author(s):  
Amna Hartiati ◽  
I. A. Mahatma Tuningrat

Tujuan umum yang ingin dicapai dari penelitian ini adalah 1) untuk mengetahui pengaruh konsentrasi pelarut dan waktu pengadukan pada karakteristik glukomanan tepung ubi talas yang diproduksi, 2) untuk mendapatkan glukomanan dengan karakteristik terbaik dari tepung  ubi  talas. Pelarut yang digunakan adalah etanol pada konsentrasi  50, 60 dan 70% dengan waktu pengadukan 30, 60 dan 90 menit. Penelitian ini menggunakan rancangan acak kelompok faktorial dengan dua faktor: konsentrasi pelarut dan waktu pengadukan selama ekstraksi tepung ubi talas. Konsentrasi pelarut yang digunakan untuk ekstraksi glukomanan terdiri dari 3 level, yaitu 50, 60 dan 70% (v / v). Waktu pengadukan selama ekstraksi terdiri dari tiga level, yaitu 30, 60 dan 90 menit. Parameter yang diamati adalah rendemen, kadar glukomanan, kadar pati dan kadar air. Penelitian ini terdiri dari 2 (dua) tahap, yaitu pembuatan glukomanan dari tepung ubi talas dan tahap kedua adalah hasil terbaik pada tahap satu yang akan digunakan sebagai bahan  edible  film buah segar. Hasil penelitian menunjukkan bahwa konsentrasi pelarut dan waktu pengadukan memiliki pengaruh yang sangat signifikan terhadap kadar glukomanan, kadar air dan interaksinya, tidak berpengaruh nyata terhadap kadar pati, rendemen glukomanan. Karakteristik terbaik glukomanan adalah perlakuan konsentrasi pelarut etanol 70% dan waktu pengadukan 90 menit dengan kadar glukomanan 60,166%; kadar pati 0,072%; kadar air 7,313% dan rendemen  9,320% untuk tepung talas.   The general objectives to be achieved from this study were: 1) to determine the effect of solvent concentration and stirring duration on the glucomannan character of Taro sweet potato flour produced; 2) to obtain glucomannan with the best characteristics of Taro sweet potato flour. The solvent used is ethanol at a concentration of 50, 60 and 70% with a stirring time of 30, 60 and 90 minutes. The study used a factorial randomized block design with two factors: solvent concentration and stirring time during the extraction of Taro sweet potato flour. The concentration of solvent used for glucomannan extraction consisted of 3 levels, namely 50, 60 and 70% (v / v). The duration of stirring during extraction consists of three levels, namely 30, 60 and 90 minutes. The parameters observed were the yield, glucomannan content, starch content, and water content. This study consisted of 2 (two) stages, namely the manufacture of glucomannan from Taro sweet potato flour and the second stage was the best result in stage one would be used as an edible film chart on fresh fruit. The results showed that solvent concentration and stirring time had a very significant effect on glucomannan content, water content, and interaction and did not significantly affect starch content, the yield of glucomannan Taro flour. The best characteristics of glucomannan were the treatment of 70% ethanol solvent concentration and stirring time of 90 minutes with glucomannan content of 60.116%; 0.072% starch content; moisture content 7.313% and 9.320% yield for Taro yam flour.  


2015 ◽  
Vol 39 (3) ◽  
pp. 419-426 ◽  
Author(s):  
Md Golam Azam ◽  
Umakanta Sarker ◽  
Maniruzzam ◽  
Bhagya Rani Banik

This experiment was conducted in a randomized block design with three replications at Bangladesh Agricultural Research Institute, Gazipur-1701 during the rabi season of 2010 with 25 maize inbred lines. Correlation and path coefficient analysis were done for yield and some other traits. Genotypic variations were observed for ear height and grains/row. The highest broad sense heritability (h2b) was observed for yield/plant followed by ear height and 1000- grain weight. Maximum genetic advance in percentage of mean (GA) was recorded for yield/plant (92.652) and ear height (75.87). The yield/plant showed significant positive genotypic correlation (rg) with cob diameter (0.440) and grains/row (0.265). Significant negative correlation was observed between ear height and yield and also for days to 50% tasseling. The highest direct positive effect was obtained for rows/cob. These studies suggest that cob diameter, row per cob, grains/row and ear height were the most important yield contributing factors and an attempt should, therefore, be made for an effective selection of these traits. DOI: http://dx.doi.org/10.3329/bjar.v39i3.21985 Bangladesh J. Agril. Res. 39(3): 419-426, September 2014


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