Influence of low fertility and vine killing on sugar development in apical and basal portions of Russet Burbank potatoes

1978 ◽  
Vol 55 (5) ◽  
pp. 239-246 ◽  
Author(s):  
W. M. Iritani ◽  
L. Weller
Keyword(s):  
Russet Burbank ◽  
Low Fertility ◽  
Vine Killing ◽  
Sugar Development

scholarly journals Influence of Timing of Harvest in Relation to Haulm Killing and Planting Date on Potato Tuber Rot Caused by Phytophthora infestans

Plant Disease ◽  
2002 ◽  
Vol 86 (3) ◽  
pp. 264-268 ◽  
Author(s):  
J. S. Miller ◽  
T. F. Cummings ◽  
L. J. Mikitzel ◽  
D. A. Johnson
Keyword(s):  
Late Blight ◽  
Phytophthora Infestans ◽  
Planting Date ◽  
Russet Burbank ◽  
Vine Killing ◽  
Ranger Russet ◽  
Tuber Blight ◽  
Two Samples ◽  
Haulm Killing ◽  
Tuber Rot

Killing potato haulms 2 to 3 weeks prior to harvesting tubers is recommended for the management of potato late blight to eliminate the foliage as a source of tuber blight inoculum. Some potato growers in the Columbia Basin of Washington and Oregon, however, harvest tubers within days of killing potato haulms or harvest tubers without killing potato haulms. The susceptibility of potato tubers harvested from green haulms to late blight is unknown. From 1996 to 1998, Russet Burbank and Ranger Russet seed tuber pieces were planted on three different dates and then harvested simultaneously to obtain daughter tubers at different levels of maturity as determined by physiological degree day (P-day) accumulation. Tubers from two trials in 1996 were harvested within 1 to 4 days of haulm killing, tubers from a single trial in 1997 were harvested 16 days after haulm killing, and tubers from two trials in 1998 were harvested 1 and 21 days after haulm killing. Tubers from each plot were divided into two samples; one sample was inoculated the day after harvest and the other sample was inoculated 6 months after harvest on the buds and periderm tissue with a US-8 isolate of Phytophthora infestans. Severity of tuber blight on tuber surfaces and internal tuber tissue was highly correlated. When tubers were harvested within 1 to 4 days after haulm kill, the youngest tubers had the highest percentage of skinning and the lowest percentage of tuber blight. These tests, however, were not designed to test the hypothesis that increased tuber skinning resulted in increased tuber rot. Severity of tuber blight was greater for Ranger Russet tubers than for Russet Burbank tubers. The correlation between the severity of tuber blight at harvest and after 6 months in storage was significant. In some cases, differences in susceptibility to tuber blight due to planting date were observed after 6 months in storage. When tubers were harvested within 1 to 4 days after vine killing, tubers from plants that had been growing longer were more susceptible to late blight tuber rot than tubers from plants that had been growing for a shorter period of time.

Low Fertility in Europe: Is There Still Reason to Worry?

2011 ◽  
Author(s):  
Stijn Hoorens ◽  
Jack Clift ◽  
Laura Staetsky ◽  
Barbara Janta ◽  
Stephanie Diepeveen ◽  
...  
Keyword(s):  
Low Fertility

Quantifying the value proposition for white clover persistence on a New Zealand summer-dry hill-country farm

2020 ◽  
Vol 82 ◽  
pp. 199-209
Author(s):  
Mike B. Dodd ◽  
Katherine N. Tozer ◽  
Iris Vogeler ◽  
Rose Greenfield ◽  
David R. Stevens ◽  
...  
Keyword(s):  
White Clover ◽  
Net Present Value ◽  
Moisture Stress ◽  
Simulation Modelling ◽  
Low Fertility ◽  
System Modelling ◽  
Value Proposition ◽  
Hill Country ◽  
The North ◽  
Farm System

The improvement in forage quality and quantity of summer-dry hill country pasture resulting from the introduction of clover is well recognised. However, ensuring the persistence of the commonly availablecultivars is challenging, in the face of seasonal moisture stress, intensive grazing, competition from established well-adapted pasture species, low soil fertility and low soil pH – conditions typical of the East Coast of the North Island. Here we quantify the value proposition associated with the introduction of white clover into a case study on a Gisborne sheep and beef farm, using a six-step process. A topographically explicit approach is taken, using an understanding of the underlying spatial variability, based on a combination of soil and pasture measurements, APSIM simulation modelling of pasture growth and farm system modelling of enterprise performance. We show that from a baseline of a typical low-fertility, diverse species hill country pasture, white clover introduction can increase spring and summer forage consumption by 17%, enabling inclusion of an additional 6-month bull finishing enterprise generating a 32% greater carcass weight production and leading to a 49% improvement in farm system EBIT. This represents a positive net present value of over $360,000 for the original investment in white clover establishment into existing pastures.

ON-FARM FORESTRY DEVELOPMENT OPTIONS FOR NORTHLAND

1986 ◽  
pp. 27-32
Author(s):  
J.S. Clark
Keyword(s):  
Joint Ventures ◽  
Low Fertility ◽  
High Fertility ◽  
Financial Returns ◽  
Farm Forestry ◽  
Hill Country ◽  
Financial Position ◽  
On Farm

Agroforests and woodlots offer Northland hill country farmers investment and diversification opportunities. Agroforests have less effect on the "whole farm" financial position than woodlots, especially where a progressive planting regime is adopted and where no further borrowing is required. Establishment and tending costs for agro-forests are lower, and returns come much sooner. The proven opportunity for continued grazing under trees established in this manner, apart from a short post-planting period, further enhances the agroforesty option. Even where there is reluctance on a farmer's part to plant trees on high fertility land, the expected financial returns from agroforests on low and medium fertility land will increase the overall long-term profitability and flexibility of the whole farming operation. Woodlots may be more appropriate on low fertility areas where weed reversion is likely. Joint ventures may be worth considering where farm finances are a limited factor. Keywords: On-farm forestry development, Northland hill country, agroforestry, woodlots, diversification, joint ventures, progressive planting regimes, grazing availability.

PASTURE ESTABLISHMENT ON EAST COAST NORTH ISLAND HILL COUNTRY

1984 ◽  
pp. 216-218
Author(s):  
B.J. Arnst ◽  
O.L. Park
Keyword(s):  
White Clover ◽  
Carrying Capacity ◽  
Return On Investment ◽  
East Coast ◽  
Close Association ◽  
Development Programme ◽  
Low Fertility ◽  
Stock Management ◽  
Hill Country

Large areas of North Island hill country are producing below potential as a result of low fertility and poor pasture composition. Removal of undesirable species and replacement with a higher producing pasture is essential for increased productivity but is difficult to achieve. A development programme is described where the use of glyphosate in close association with oversowing and stock management has allowed rapid pasture establishment, marked increase in carrying capacity and a quick return on investment. Keywords: Pasture establishment, glyphosate, oversowing, white clover, subdivision, productivity.

A Critical Review on Paradigm Shift in Policy Responses to Low Fertility

2018 ◽  
Vol 8 (2) ◽  
pp. 36-64
Author(s):  
Sungho Chung
Keyword(s):  
Critical Review ◽  
Paradigm Shift ◽  
Low Fertility ◽  
Policy Responses
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