Pub Date : 1988-01-01DOI: 10.1080/03015521.1988.10425617
D. Barker, D. Zhang, A. Mackay
Abstract In a preliminary study, root distribution, biomass, length, and surface area were measured to a depth of 800 mm in mid summer on a sunny (north) and shady (south) aspect of a low fertility hill country sward grazed by sheep. The dominant grass species were browntop (Agrostis capillaris L.), crested dogstail (Cynosurus cristatus L.), and yorkshire fog (Holcus lanatus L.). White clover (Trifolium repens L.), suckling clover (T. dubium Sibth. L.)( and lotus (Lotus pedunculatus Cav.) were the dominant legume species. Calculated root biomass for the profile down to 800 mm was 14 410 kg dry matter (DM)/ha on the shady face and 21 470 kg DM/ha on the sunny face. This was 2.3–3.5 times more than above-ground biomass produced on an annual basis and 6–7 times the total above-ground pasture biomass at the times of sampling. The large root biomass, and consequently the large quantities of nutrients involved in the below-ground component of the nutrient cycle, highlight the need for further research to quanti...
{"title":"Root distribution in a low fertility hill country sward grazed by sheep","authors":"D. Barker, D. Zhang, A. Mackay","doi":"10.1080/03015521.1988.10425617","DOIUrl":"https://doi.org/10.1080/03015521.1988.10425617","url":null,"abstract":"Abstract In a preliminary study, root distribution, biomass, length, and surface area were measured to a depth of 800 mm in mid summer on a sunny (north) and shady (south) aspect of a low fertility hill country sward grazed by sheep. The dominant grass species were browntop (Agrostis capillaris L.), crested dogstail (Cynosurus cristatus L.), and yorkshire fog (Holcus lanatus L.). White clover (Trifolium repens L.), suckling clover (T. dubium Sibth. L.)( and lotus (Lotus pedunculatus Cav.) were the dominant legume species. Calculated root biomass for the profile down to 800 mm was 14 410 kg dry matter (DM)/ha on the shady face and 21 470 kg DM/ha on the sunny face. This was 2.3–3.5 times more than above-ground biomass produced on an annual basis and 6–7 times the total above-ground pasture biomass at the times of sampling. The large root biomass, and consequently the large quantities of nutrients involved in the below-ground component of the nutrient cycle, highlight the need for further research to quanti...","PeriodicalId":19285,"journal":{"name":"New Zealand journal of experimental agriculture","volume":"51 1","pages":"73-76"},"PeriodicalIF":0.0,"publicationDate":"1988-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74152259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1988-01-01DOI: 10.1080/03015521.1988.10425612
P. Gandar, K. A. Hughes
Abstract Root-length densities (RLD; root length per unit volume of soil) were measured in core samples taken from nine North Island kiwifruit orchards. Despite differences in vine spacings, root-stock ages and types, soils, climates, and management, there was a consistent pattern to root systems. In orchards younger than 10 years, roots explored bowl-shaped soil volumes and mean RLD fell with both depth and radial distance from vines. In older orchards, root systems of adjacent plants met so that soil volumes available to plants were completely explored and mean RLD fell with depth. Roots were found at depths greater than 1 m in most orchards. In both young and old orchards, RLD ranged from 0 to 8 cm/cm3 but proportions of zero values increased towards the peripheries of root systems. These proportions were used to subdivide rooting volumes into volumes of total occupancy in which all RLD were greater than zero, and volumes of partial occupancy in which volumes containing roots were interspersed with ‘vo...
根长密度(RLD;在9个北岛猕猴桃果园的核心样品中测量了单位体积土壤的根长。尽管在葡萄藤间距、砧木年龄和类型、土壤、气候和管理方面存在差异，但根系的模式是一致的。在10年以下的果园中，根系探索碗状土壤体积，平均RLD随深度和距离葡萄藤的径向距离而下降。在较老的果园中，相邻植物的根系相互接触，使植物可利用的土壤体积得到充分挖掘，平均RLD随深度而下降。在大多数果园中，根的深度大于1 m。幼果园和老果园的RLD均在0 ~ 8 cm/cm3之间，但在根系边缘，零值的比例增加。利用这些比例将生根体积细分为所有RLD都大于零的总占用体积和部分占用体积，其中包含根的体积中散布着' vo '。
{"title":"Kiwifruit root systems 1. Root-length densities","authors":"P. Gandar, K. A. Hughes","doi":"10.1080/03015521.1988.10425612","DOIUrl":"https://doi.org/10.1080/03015521.1988.10425612","url":null,"abstract":"Abstract Root-length densities (RLD; root length per unit volume of soil) were measured in core samples taken from nine North Island kiwifruit orchards. Despite differences in vine spacings, root-stock ages and types, soils, climates, and management, there was a consistent pattern to root systems. In orchards younger than 10 years, roots explored bowl-shaped soil volumes and mean RLD fell with both depth and radial distance from vines. In older orchards, root systems of adjacent plants met so that soil volumes available to plants were completely explored and mean RLD fell with depth. Roots were found at depths greater than 1 m in most orchards. In both young and old orchards, RLD ranged from 0 to 8 cm/cm3 but proportions of zero values increased towards the peripheries of root systems. These proportions were used to subdivide rooting volumes into volumes of total occupancy in which all RLD were greater than zero, and volumes of partial occupancy in which volumes containing roots were interspersed with ‘vo...","PeriodicalId":19285,"journal":{"name":"New Zealand journal of experimental agriculture","volume":"62 1","pages":"35-46"},"PeriodicalIF":0.0,"publicationDate":"1988-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74642698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1988-01-01DOI: 10.1080/03015521.1988.10425610
P. Williams, A. Roberts
Abstract The potassium (K) lost through animal products (milk, calf and culled stock) and transfer of excretai K to the dairy shed and raceways, was estimated at 1.6 kg/stock unit (SU) for a dairy farmlet of small herd size, assuming the cows spend 5% of the year off the paddock. This loss increased to 2.5 kg K/SU if the cows spend 10% of the year off the paddock as is likely on a dairy farm with a larger number of cows. These values are lower than the 4 kg K/SU currently used by the Ministry of Agriculture and Fisheries as the animal loss factor (ALF) in their fertiliser advice scheme for dairying on flat-rolling country in New Zealand.
假设奶牛一年有5%的时间离开围场，通过动物产品(牛奶、小牛和被淘汰的牲畜)和粪便钾转移到奶棚和跑道的钾损失估计为1.6 kg/stock unit (SU)。如果奶牛一年中有10%的时间不在围场(奶牛数量较多的奶牛场很可能是这样)，这一损失将增加到2.5千克/千克。这些值低于目前新西兰农业和渔业部在其平坦国家的乳制品肥料建议计划中使用的4 kg K/SU作为动物损失因子(ALF)。
{"title":"Estimation of potassium losses from a grazed dairy farm in Taranaki","authors":"P. Williams, A. Roberts","doi":"10.1080/03015521.1988.10425610","DOIUrl":"https://doi.org/10.1080/03015521.1988.10425610","url":null,"abstract":"Abstract The potassium (K) lost through animal products (milk, calf and culled stock) and transfer of excretai K to the dairy shed and raceways, was estimated at 1.6 kg/stock unit (SU) for a dairy farmlet of small herd size, assuming the cows spend 5% of the year off the paddock. This loss increased to 2.5 kg K/SU if the cows spend 10% of the year off the paddock as is likely on a dairy farm with a larger number of cows. These values are lower than the 4 kg K/SU currently used by the Ministry of Agriculture and Fisheries as the animal loss factor (ALF) in their fertiliser advice scheme for dairying on flat-rolling country in New Zealand.","PeriodicalId":19285,"journal":{"name":"New Zealand journal of experimental agriculture","volume":"26 1","pages":"23-27"},"PeriodicalIF":0.0,"publicationDate":"1988-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78272202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1988-01-01DOI: 10.1080/03015521.1988.10425608
K. Carter, R. Stoker
Abstract In six experiments conducted over the six seasons from 1976/77 to 1981/82, the response of non-irrigated and irrigated ‘Greenfeast’ garden peas to phosphorus (P) and potassium (K) fertilisers was examined. All experiments were carried out on Lismore stony silt loam on sites with different histories. P fertiliser was applied as superphosphate (300 kg/ha) and K as potassium chloride (100 kg/ha). Both fertilisers were applied at drilling. Yield responses to K, P, and P + K fertiliser occurred. However, these responses were small, inconsistent, and generally uneconomic. This work shows garden peas can be grown satisfactorily and most economically without P and K fertilisers when they are part of a cropping rotation on Lismore soils that have medium to high P and K soil test values. Low soil test values are unlikely to occur on these soils with normal fertiliser applications in crop/pasture rotations.
{"title":"Responses of non-irrigated and irrigated garden peas to phosphorus and potassium on Lismore stony silt loam","authors":"K. Carter, R. Stoker","doi":"10.1080/03015521.1988.10425608","DOIUrl":"https://doi.org/10.1080/03015521.1988.10425608","url":null,"abstract":"Abstract In six experiments conducted over the six seasons from 1976/77 to 1981/82, the response of non-irrigated and irrigated ‘Greenfeast’ garden peas to phosphorus (P) and potassium (K) fertilisers was examined. All experiments were carried out on Lismore stony silt loam on sites with different histories. P fertiliser was applied as superphosphate (300 kg/ha) and K as potassium chloride (100 kg/ha). Both fertilisers were applied at drilling. Yield responses to K, P, and P + K fertiliser occurred. However, these responses were small, inconsistent, and generally uneconomic. This work shows garden peas can be grown satisfactorily and most economically without P and K fertilisers when they are part of a cropping rotation on Lismore soils that have medium to high P and K soil test values. Low soil test values are unlikely to occur on these soils with normal fertiliser applications in crop/pasture rotations.","PeriodicalId":19285,"journal":{"name":"New Zealand journal of experimental agriculture","volume":"67 1","pages":"11-15"},"PeriodicalIF":0.0,"publicationDate":"1988-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87032599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1988-01-01DOI: 10.1080/03015521.1988.10425618
C. F. Morales
Abstract Latania scale, (Hemiberlesia lataniae (Signoret)), is now established in the North Island of New Zealand. The significance of this pest and methods of distinguishing latania scale from greedy scale (Hemiberlesia rapax (Comstock)) and oleander scale (Aspidiotus nerii Bouche) are discussed.
{"title":"The occurrence of latania scale, Hemiberlesia lataniae (Signoret) (Hemiptera: Diaspididae), in New Zealand","authors":"C. F. Morales","doi":"10.1080/03015521.1988.10425618","DOIUrl":"https://doi.org/10.1080/03015521.1988.10425618","url":null,"abstract":"Abstract Latania scale, (Hemiberlesia lataniae (Signoret)), is now established in the North Island of New Zealand. The significance of this pest and methods of distinguishing latania scale from greedy scale (Hemiberlesia rapax (Comstock)) and oleander scale (Aspidiotus nerii Bouche) are discussed.","PeriodicalId":19285,"journal":{"name":"New Zealand journal of experimental agriculture","volume":"87 1","pages":"77-82"},"PeriodicalIF":0.0,"publicationDate":"1988-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87433542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1988-01-01DOI: 10.1080/03015521.1988.10425611
W. Saunders, D. M. Cooper, R. Campkin
Abstract Luxury uptake of potassium (K) from potassium chloride (KC1) by pasture plants is a major disadvantage in its use as a fertiliser for pastures. Luxury uptake shortens the fertiliser's effective life and causes excessively high concentrations of potassium relative to calcium, magnesium, and sodium. This can result in health problems for grazing stock. A further disadvantage is that KC1 is readily leached from the soil if there is heavy rain. Coating KC1 has been tried as a way of slowing the release of K and its uptake by ryegrass, and of reducing loss by leaching. Coating KC1 with sulphur reduced its rate of dissolution greatly and avoided luxury uptake by the grass. On an extremely K deficient soil there was some loss of growth relative to uncoated KC1 for 2 months, but over the next 4 months, the sulphur-coated KC1 gave higher yields. Wax-coated KC1 gave practically the same results as uncoated KC1. A leaching test was used to measure rate of solution of KC1 and its results related well to the ...
{"title":"A comparison of slow release potassium fertilisers for pasture","authors":"W. Saunders, D. M. Cooper, R. Campkin","doi":"10.1080/03015521.1988.10425611","DOIUrl":"https://doi.org/10.1080/03015521.1988.10425611","url":null,"abstract":"Abstract Luxury uptake of potassium (K) from potassium chloride (KC1) by pasture plants is a major disadvantage in its use as a fertiliser for pastures. Luxury uptake shortens the fertiliser's effective life and causes excessively high concentrations of potassium relative to calcium, magnesium, and sodium. This can result in health problems for grazing stock. A further disadvantage is that KC1 is readily leached from the soil if there is heavy rain. Coating KC1 has been tried as a way of slowing the release of K and its uptake by ryegrass, and of reducing loss by leaching. Coating KC1 with sulphur reduced its rate of dissolution greatly and avoided luxury uptake by the grass. On an extremely K deficient soil there was some loss of growth relative to uncoated KC1 for 2 months, but over the next 4 months, the sulphur-coated KC1 gave higher yields. Wax-coated KC1 gave practically the same results as uncoated KC1. A leaching test was used to measure rate of solution of KC1 and its results related well to the ...","PeriodicalId":19285,"journal":{"name":"New Zealand journal of experimental agriculture","volume":"8 1","pages":"29-33"},"PeriodicalIF":0.0,"publicationDate":"1988-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85591766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1987-10-01DOI: 10.1080/03015521.1987.10425596
G. Scobie, N. St-Pierre
Abstract A scheme, recently introduced in New Zealand, for generating phosphorus fertiliser recommendations estimates the amount of phosphorus nutrient needed to be applied to maintain the size of the cycling pool constant. This scheme was extended by developing an integrated model of pasture response/utilisation and animal production to determine the most profitable long-run combination of fertiliser application and animal output. The economic consequences of imperfect information about the parameters were analysed.
{"title":"Economics of phosphorus fertiliser use on pastures 1. Long-run maintenance requirements","authors":"G. Scobie, N. St-Pierre","doi":"10.1080/03015521.1987.10425596","DOIUrl":"https://doi.org/10.1080/03015521.1987.10425596","url":null,"abstract":"Abstract A scheme, recently introduced in New Zealand, for generating phosphorus fertiliser recommendations estimates the amount of phosphorus nutrient needed to be applied to maintain the size of the cycling pool constant. This scheme was extended by developing an integrated model of pasture response/utilisation and animal production to determine the most profitable long-run combination of fertiliser application and animal output. The economic consequences of imperfect information about the parameters were analysed.","PeriodicalId":19285,"journal":{"name":"New Zealand journal of experimental agriculture","volume":"55 1","pages":"435-443"},"PeriodicalIF":0.0,"publicationDate":"1987-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77362486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1987-10-01DOI: 10.1080/03015521.1987.10425601
J. Scheffer, G. J. Wilson
Abstract Field experiments were conducted at Pukekohe, New Zealand, to compare the effectiveness of molybdenum (Mo) incorporated in a seed pellet (at rates from 24 to 466 g Mo/kg of seed) with a standard foliar spray (1025 g Mo/ha) in meeting the Mo requirements of seedlings of cauliflower (Brassica oleracea L. var. botrytis L.). Very low rates of Mo incorporated in the seed pellet (e.g., 24 g Mo/kg seed) alleviated any Mo deficiency, whereas Mo toxicity resulted when ⩾117 g Mo/kg seed was incorporated. Cultivars differed in their sensitivity to Mo deficiency and toxicity. The implications of these results for practical control of Mo deficiency are discussed.
摘要在新西兰Pukekohe进行了田间试验，比较了种子颗粒(24 ~ 466 g Mo/kg)与标准叶面喷施(1025 g Mo/ha)对花菜(Brassica oleracea L. var. botrytis L.)幼苗钼需要量的影响。极低的Mo在种子颗粒中的掺入率(例如，24 g Mo/kg种子)减轻了任何Mo缺乏症，而当掺入大于或等于117 g Mo/kg种子时，会产生Mo毒性。不同品种对缺钼的敏感性和毒性存在差异。讨论了这些结果对实际控制缺钼的意义。
{"title":"Cauliflower: Molybdenum application using pelleted seed and foliar sprays","authors":"J. Scheffer, G. J. Wilson","doi":"10.1080/03015521.1987.10425601","DOIUrl":"https://doi.org/10.1080/03015521.1987.10425601","url":null,"abstract":"Abstract Field experiments were conducted at Pukekohe, New Zealand, to compare the effectiveness of molybdenum (Mo) incorporated in a seed pellet (at rates from 24 to 466 g Mo/kg of seed) with a standard foliar spray (1025 g Mo/ha) in meeting the Mo requirements of seedlings of cauliflower (Brassica oleracea L. var. botrytis L.). Very low rates of Mo incorporated in the seed pellet (e.g., 24 g Mo/kg seed) alleviated any Mo deficiency, whereas Mo toxicity resulted when ⩾117 g Mo/kg seed was incorporated. Cultivars differed in their sensitivity to Mo deficiency and toxicity. The implications of these results for practical control of Mo deficiency are discussed.","PeriodicalId":19285,"journal":{"name":"New Zealand journal of experimental agriculture","volume":"74 1","pages":"485-490"},"PeriodicalIF":0.0,"publicationDate":"1987-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83268371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1987-10-01DOI: 10.1080/03015521.1987.10425594
K. Macmillan, V. R. Carruthers, K. Bremner, H. Henderson
Abstract ‘Cups-on time’ (COT) for individual Jersey cows was measured using two techniques during six consecutive milkings in 2 consecutive weeks during peak lactation (October–November). Four groups of 15 animals included two groups with a high breeding index (HBI) of 127 and two groups with a low breeding index (LBI) of 101. HBI cows averaged 15.5 kg milk/day compared to 12.5 kg/day for the LBI cows. Morning (AM) milk weights for all groups were twice the afternoon (PM) milk weights at milking intervals of 16:8 h. The average COT at AM milkings was 7.6 min/cow compared to 5.7 min/cow at PM milkings. The average flow rate (AFR) at AM milkings was 1.33 kg/min for HBI cows and 1.13 kg/min for LBI cows. Comparable AFRs at PM milkings were 0.88 (HBI) and 0.75 kg/min (LBI). Differences related to BI in COT and AFR were not statistically significant, partly because of the large variation among individual cows within a BI group. This study showed that the increased production of Jersey cows resulting from the u...
{"title":"Some milking characteristics of Jersey cows of differing breeding index","authors":"K. Macmillan, V. R. Carruthers, K. Bremner, H. Henderson","doi":"10.1080/03015521.1987.10425594","DOIUrl":"https://doi.org/10.1080/03015521.1987.10425594","url":null,"abstract":"Abstract ‘Cups-on time’ (COT) for individual Jersey cows was measured using two techniques during six consecutive milkings in 2 consecutive weeks during peak lactation (October–November). Four groups of 15 animals included two groups with a high breeding index (HBI) of 127 and two groups with a low breeding index (LBI) of 101. HBI cows averaged 15.5 kg milk/day compared to 12.5 kg/day for the LBI cows. Morning (AM) milk weights for all groups were twice the afternoon (PM) milk weights at milking intervals of 16:8 h. The average COT at AM milkings was 7.6 min/cow compared to 5.7 min/cow at PM milkings. The average flow rate (AFR) at AM milkings was 1.33 kg/min for HBI cows and 1.13 kg/min for LBI cows. Comparable AFRs at PM milkings were 0.88 (HBI) and 0.75 kg/min (LBI). Differences related to BI in COT and AFR were not statistically significant, partly because of the large variation among individual cows within a BI group. This study showed that the increased production of Jersey cows resulting from the u...","PeriodicalId":19285,"journal":{"name":"New Zealand journal of experimental agriculture","volume":"31 1","pages":"425-428"},"PeriodicalIF":0.0,"publicationDate":"1987-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87331439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1987-10-01DOI: 10.1080/03015521.1987.10425603
J. M. Follett, J. Douglas
Abstract Growth of asparagus seedlings when grown in seven solutions with varying nitrate: ammonium ratios (NO3 -: NH4 +) was compared. The proportion of N present as NO3 - ranged from 100% to 50%. Asparagus grew best in NO3 - dominated solutions with maximum shoot and root growth occurring with NO3 -: NH4 + mixtures containing nitrogen as 17–40% NH4 +. Significant reductions in growth occurred with either 100% NO3 - or 50% NH4 +.
{"title":"Effect of nitrate:Ammonium ratios on growth of asparagus seedlings in sand culture","authors":"J. M. Follett, J. Douglas","doi":"10.1080/03015521.1987.10425603","DOIUrl":"https://doi.org/10.1080/03015521.1987.10425603","url":null,"abstract":"Abstract Growth of asparagus seedlings when grown in seven solutions with varying nitrate: ammonium ratios (NO3 -: NH4 +) was compared. The proportion of N present as NO3 - ranged from 100% to 50%. Asparagus grew best in NO3 - dominated solutions with maximum shoot and root growth occurring with NO3 -: NH4 + mixtures containing nitrogen as 17–40% NH4 +. Significant reductions in growth occurred with either 100% NO3 - or 50% NH4 +.","PeriodicalId":19285,"journal":{"name":"New Zealand journal of experimental agriculture","volume":"153 1","pages":"497-499"},"PeriodicalIF":0.0,"publicationDate":"1987-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73991097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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