scholarly journals Management of Primocane-fruiting Blackberry: Impacts on Yield, Fruiting Season, and Cane Architecture

HortScience ◽  
2012 ◽  
Vol 47 (5) ◽  
pp. 593-598 ◽  
Author(s):  
Bernadine C. Strik ◽  
John R. Clark ◽  
Chad E. Finn ◽  
Gil Buller
Keyword(s):  
Early Spring ◽  
Management Systems ◽  
High Yield ◽  
Late Winter ◽  
Growing Degree Days ◽  
Degree Days ◽  
Branch Number ◽  
Node Number ◽  
Berry Weight

Primocane management systems were compared for ‘Prime-Jan’® and ‘Prime-Jim’®, primocane-fruiting blackberry (Rubus L. subgenus Rubus, Watson), grown in a field planting in Aurora, OR. Treatments studied were: 1) no manipulation of primocanes (untipped; no floricanes); 2) untipped primocanes growing in the presence of floricanes; 3) untipped primocanes grown with rowcover in late winter to early spring; and 4) primocanes “soft-tipped” at 1 m to encourage branching. Date of primocane first bloom and cane height at bloom were unaffected by cultivar and were only affected by primocane management in 2005. The number of growing degree-days to first bloom ranged from 1272 to 1390 depending on year. Primocane management did not affect ovule or drupelet number per berry or percent drupelet set. ‘Prime-Jim’ had more drupelets and greater weight per berry in 2005 than ‘Prime-Jan’. Fruit harvested earlier in the season had more ovules and drupelets than later harvested fruit in 2004. Primocanes that grew in the presence of floricanes were longer and bloomed later but did not differ in yield from untipped canes grown only for a primocane crop. Use of rowcover in 2005 advanced bloom and harvest, improving yield 73% compared with untipped control canes. Soft-tipping primocanes increased yield 114% to 150% compared with untipped canes (5.6 vs. 2.4 t·ha−1) through increasing branch and node number per cane and percentage of fruiting nodes; soft-tipping did not delay harvest. Yield/cane was negatively correlated with the number of fruiting canes/plot but positively correlated with branches/cane, total branch and cane length, number of nodes and percent fruiting nodes, fruit/cane, and berry weight. The proportion of fruiting nodes was greater on branches than on the main cane illustrating the importance of managing this type of blackberry to increase branch number for high yield.

Primordia and leaf production in winter wheat, triticale, and rye under field conditions

1986 ◽  
Vol 64 (9) ◽  
pp. 1972-1976 ◽  
Author(s):  
L. A. Hunt ◽  
Anne-Marie Chapleau
Keyword(s):  
Winter Wheat ◽  
Triticum Aestivum L ◽  
Early Spring ◽  
Field Conditions ◽  
Late Winter ◽  
Winter Rye ◽  
Degree Days ◽  
Leaf Production ◽  
Winter Triticale ◽  
Leaf Emergence

Primordia production and leaf emergence were investigated in winter wheat (Triticum aestivum L. em Thell.) and two related species, winter rye (Secale cereale L.) and winter triticale (× Triticosecale Wittmack), under field conditions in Southern Ontario, a region with a humid continental climate. Primordia initiation could be adequately described by a linear regression of primordia number on accumulated degree-days in the 1st year of study, 1981 – 1982. In the 2nd year, however, a linear relationship was noticed only in the late winter and early spring, with the rate of primordia production being distinctly lower earlier in the season. The rate of primordia initiation was faster in the ryes than in the wheats, a superiority which was associated with greater spikelet production. Triticale had an intermediate rate of primordia initiation but was closer to wheat in the timing of double ridge and terminal spikelet formation. Leaves emerged at a constant rate (degree-days base) which was similar in most of the cultivars.

Hazelnut floral phenology in southern Ontario

2021 ◽  
Author(s):  
Toktam Taghavi ◽  
Alireza Rahemi ◽  
Adam Dale ◽  
Dragan Galic ◽  
John M. Kelly
Keyword(s):  
Early Spring ◽  
Growing Degree Days ◽  
Degree Days ◽  
Southern Ontario ◽  
Floral Phenology ◽  
Male Flowers ◽  
Compatible Pollen ◽  
Pollen Shed ◽  
Continental Climate ◽  
Female Flowers

Hazelnut (Corylus avellana) is a monoecious, dichogamous plant species that flowers in winter and early spring. In traditional hazelnut growing regions, hazelnut cultivars generally express protandry where the male flowers bloom before the female flowers. Nut set requires that compatible pollen be shed when the stigmas of the main cultivar are receptive. In this study, the floral phenology and date of leaf budbreak of five selections and 19 hazelnut cultivars from Europe and North America were observed over four years in southern Ontario, and results were compared with cumulative growing degree days. In the continental climate of southern Ontario, most cultivars showed protogyny. Flowering dates varied over the years with pollination occurring in a period of 2 - 3 weeks in early spring. These cultivars were classified into early, mid, and late blooming types. A growing degree day model was a better tool than average daily temperatures to predict the flowering dates of catkins and female flowers. Averaged over years, most of the cultivars in this study have a female bloom that is likely too early for the pollen shed by most of the other cultivars. This would likely impact yields in a commercial orchard. However, ‘Jefferson’, ‘Gene’, and ‘Epsilon’ have late females that are receptive when other cultivars are shedding pollen.

Evaluation of Finger Millet Varieties under Rainfed Condition of Eastern India

2017 ◽  
Vol 4 (03) ◽  
Author(s):  
M. K. Singh ◽  
VINOD KUMAR ◽  
SHAMBHU PRASAD
Keyword(s):  
Field Experiment ◽  
Finger Millet ◽  
Yield Potential ◽  
Growing Degree Days ◽  
Eastern India ◽  
Degree Days ◽  
Rainfed Condition ◽  
Net Returns ◽  
Humid Environment ◽  
Use Efficiency

A field experiment was carried out during the kharif of 2014 and 2015 to evaluate the yield potential, economics and thermal utilization in eleven finger millet varieties under the rainfed condition of the sub-humid environment of South Bihar of Eastern India. Results revealed that the significantly higher grain yield (20.41 q ha-1), net returns (Rs 25301) and B: C ratio (1.51) was with the finger millet variety ‘GPU 67’ but was being at par to ‘GPU28’and ‘RAU-8’, and significantly superior over remaining varieties. The highest heat units (1535.1oC day), helio-thermal units (7519.7oC day hours), phenothermal index (19.4 oC days day-1) were recorded with variety ‘GPU 67’ followed by ‘RAU 8’ and ‘GPU 28’ and lowest in ‘VL 149’ at 50 % anthesis stage. Similarly, the highest growing degree days (2100 oC day), helio-thermal units (11035.8 oC day hours) were noted with ‘GPU 67’ followed by ‘RAU 8’ and ‘GPU 28’ at maturity. The highest heat use efficiency (0.97 kg ha-1 oC day) and helio-thermal use efficiency (0.19 kg ha-1 oC day hour) were in ‘GPU 67’ followed by ‘VL 315’.

scholarly journals Determining the critical period for weed control in high-yielding cotton using common sunflower as a mimic weed

2019 ◽  
Vol 33 (6) ◽  
pp. 800-807 ◽  
Author(s):  
Graham W. Charles ◽  
Brian M. Sindel ◽  
Annette L. Cowie ◽  
Oliver G. G. Knox
Keyword(s):  
Weed Control ◽  
Critical Period ◽  
Yield Loss ◽  
Field Studies ◽  
Growing Degree Days ◽  
Degree Days ◽  
Weed Density ◽  
High Level ◽  
The Cost ◽  
Planting Season

AbstractField studies were conducted over six seasons to determine the critical period for weed control (CPWC) in high-yielding cotton, using common sunflower as a mimic weed. Common sunflower was planted with or after cotton emergence at densities of 1, 2, 5, 10, 20, and 50 plants m−2. Common sunflower was added and removed at approximately 0, 150, 300, 450, 600, 750, and 900 growing degree days (GDD) after planting. Season-long interference resulted in no harvestable cotton at densities of five or more common sunflower plants m−2. High levels of intraspecific and interspecific competition occurred at the highest weed densities, with increases in weed biomass and reductions in crop yield not proportional to the changes in weed density. Using a 5% yield-loss threshold, the CPWC extended from 43 to 615 GDD, and 20 to 1,512 GDD for one and 50 common sunflower plants m−2, respectively. These results highlight the high level of weed control required in high-yielding cotton to ensure crop losses do not exceed the cost of control.

scholarly journals Responses of Branch Number and Yield Component of Soybean Cultivars Tested in Different Planting Densities

Agriculture ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 69
Author(s):  
Cailong Xu ◽  
Ruidong Li ◽  
Wenwen Song ◽  
Tingting Wu ◽  
Shi Sun ◽  
...  
Keyword(s):  
Key Management ◽  
Management Practices ◽  
Yield Component ◽  
Planting Density ◽  
Yield Potential ◽  
High Yield ◽  
Branch Number ◽  
Soybean Yield ◽  
Soybean Cultivars ◽  
Pod Number

Increasing planting density is one of the key management practices to enhance soybean yield. A 2-yr field experiment was conducted in 2018 and 2019 including six planting densities and two soybean cultivars to determine the effects of planting density on branch number and yield, and analyze the contribution of branches to yield. The yield of ZZXA12938 was 4389 kg ha−1, which was significantly higher than that of ZH13 (+22.4%). In combination with planting year and cultivar, the soybean yield increased significantly by 16.2%, 31.4%, 41.4%, and 46.7% for every increase in density of 45,000 plants ha−1. Yield will not increase when planting density exceeds 315,000 plants ha−1. A correlation analysis showed that pod number per plant increased with the increased branch number, while pod number per unit area decreased; thus, soybean yield decreased. With the increase of branch number, the branch contribution to yield increased first, and then plateaued. ZH13 could produce a high yield under a lower planting density due to more branches, while ZZXA12938 had a higher yield potential under a higher planting density due to the smaller branch number and higher tolerance to close planting. Therefore, seed yield can be increased by selecting cultivars with a little branching capacity under moderately close planting.

scholarly journals Performance of Strawberry Varieties Developed for Perennial Matted-Row Production in Annual Plasticulture in a Cold Climate Region

Agronomy ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1407
Author(s):  
Courtney A. Weber
Keyword(s):  
Large Scale ◽  
Fruit Size ◽  
Weather Conditions ◽  
Cold Climate ◽  
Annual Production ◽  
High Yield ◽  
Production Cycle ◽  
Late Season ◽  
Berry Weight ◽  
High Yields

Annual plasticulture production of strawberries promises superior weed control, fruit quality and yields. However, strawberry varieties adapted for perennial, matted-row production and local markets in cold climate regions have not been widely tested for adaptation to an annual production cycle. Productivity of seven short-day varieties developed for matted-row and/or annual production was examined in an annual plasticulture system in two consecutive trials in central NY (lat. 42.87° N, long. 76.99° W) harvested in 2013 and 2014. ‘Flavorfest’ demonstrated good performance in Trial 1 with high yield (390 g/plant) and large fruit size (13.9 g mean berry weight). ‘Jewel’ was shown to be well adapted to the annual plasticulture system with consistently high yields (330 and 390 g/plant) that equaled or surpassed other varieties and had moderate fruit size. ‘Chandler’ performed similarly to previous trials conducted in warmer regions with yield (340 g/plant) and fruit size (9.8 g mean berry weight) similar to ‘Jewel’. ‘Clancy’ yielded less but was consistent from year to year. The late season varieties Seneca and Ovation showed marked variability between years, possibly due to drastically different temperatures during flowering and fruit development in Trial 1 compared to Trial 2. High temperatures in Trial 1 likely caused higher early fruit yield, a compressed season and a precipitous decline in fruit size in the later season, thus reducing yield in the late season. Survival after a second dormant period was poor resulting in a small second harvest and reduced fruit size. Overall, the system demonstrated many of the expected benefits but may be more sensitive to weather conditions in the region. While many varieties developed for matted-row production may work well in an annual plasticulture system, not all varieties are equally adapted. Performance of each variety should be determined independently before large scale adoption by growers.

Seasonal activity and estivation of lumbricid earthworms in the midlands of Tasmania

Soil Research ◽  
1994 ◽  
Vol 32 (6) ◽  
pp. 1355 ◽  
Author(s):  
RB Garnsey
Keyword(s):  
Soil Moisture ◽  
Adult Development ◽  
Survival Rates ◽  
Soil Surface ◽  
Early Spring ◽  
Lumbricus Rubellus ◽  
Late Winter ◽  
Cocoon Production ◽  
Density And Biomass ◽  
Earthworm Activity

Earthworms have the ability to alleviate many soil degradational problems in Australia. An attempt to optimize this resource requires fundamental understanding of earthworm ecology. This study reports the seasonal changes in earthworm populations in the Midlands of Tasmania (<600 mm rainfall p.a.), and examines, for the first time in Australia, the behaviour and survival rates of aestivating earthworms. Earthworms were sampled from 14 permanent pastures in the Midlands from May 1992 to February 1994. Earthworm activity was significantly correlated with soil moisture; maximum earthworm activity in the surface soil was evident during the wetter months of winter and early spring, followed by aestivation in the surface and subsoils during the drier summer months. The two most abundant earthworm species found in the Midlands were Aporrectodea caliginosa (maximum of 174.8 m-2 or 55.06 g m-2) and A. trapezoides (86 m-2 or 52.03 g m-2), with low numbers of Octolasion cyaneum, Lumbricus rubellus and A. rosea. The phenology of A. caliginosa relating to rainfall contrasted with that of A. trapezoides in this study. A caliginosa was particularly dependent upon rainfall in the Midlands: population density, cocoon production and adult development of A. caliginosa were reduced as rainfall reduced from 600 to 425 mm p.a. In contrast, the density and biomass of A. trapezoides were unaffected by rainfall over the same range: cocoon production and adult development continued regardless of rainfall. The depth of earthworm aestivation during the summers of 1992-94 was similar in each year. Most individuals were in aestivation at a depth of 150-200 mm, regardless of species, soil moisture or texture. Smaller aestivating individuals were located nearer the soil surface, as was shown by an increase in mean mass of aestivating individuals with depth. There was a high mortality associated with summer aestivation of up to 60% for juvenile, and 63% for adult earthworms in 1993 in the Midlands. Cocoons did not survive during the summers of 1992 or 1994, but were recovered in 1993, possibly due to the influence of rainfall during late winter and early spring.

TEMPERATURE RESISTANCE OF GOLDFISH MAINTAINED UNDER CONTROLLED PHOTOPERIODS

1959 ◽  
Vol 37 (4) ◽  
pp. 419-428 ◽  
Author(s):  
William S. Hoar ◽  
G. Beth Robertson
Keyword(s):  
Temperature Change ◽  
Seasonal Variations ◽  
Rapid Growth ◽  
Endocrine System ◽  
Early Spring ◽  
Late Winter ◽  
Thyroid Activity ◽  
Temperature Resistance ◽  
Sudden Temperature Change

Goldfish maintained under controlled photoperiods for 6 weeks or longer were relatively more resistant to a sudden elevation in temperature when the daily photoperiods had been long (16 hours) and relatively more resistant to sudden chilling when they had been short (8 hours). The magnitude of the effect varied with the season. Thyroid activity was slightly greater in fish maintained under the shorter photoperiods. The longer photoperiods stimulated more rapid growth of ovaries during late winter and early spring. The endocrine system is considered a link in the chain of events regulating seasonal variations in resistance to sudden temperature change.

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