柴达木地区胡萝卜配方施肥试验

以胡萝卜肉质直根产量为主要指标,采用3414配方施肥设计进行试验,确定柴达木地区胡萝卜高产的最佳施肥措施。结果表明:在柴达木地区随着氮肥施肥量的增加,胡萝卜的产量逐渐增加,但当施肥量增加到一定程度时,胡萝卜的产量达到最大,之后随着氮肥的增加开始降低;磷、钾肥也表现出此规律,对胡萝卜产量影响依次为氮磷钾;磷钾配合对胡萝卜产量的作用最大。最佳经济效益时667m2的胡萝卜产量达到5 125.2kg,此时的氮肥、磷肥和钾肥最优组合为尿素55.2kg,过磷酸钙171.7kg,氯化钾16.1kg。     

An Automatic Device for The Control of Day Length

The effects of cover crops and NPK fertilizers (in factorial combination) on the growth, crop yield and leaf-nutrient composition of young Cox’s Orange Pippin and Worcester Pearmain apple trees have been studied over a period of six years. The covers used were : (a) wild white clover, S. 184,-(b) perennial rye-grass (Lolium perenne, S.23), (c) timothy grass (Phleum pratense, S.50), and (d) natural sward as it developed (mainly Poa annua and Agrostis stolonifera).

The major effects were due to cover crops. Nitrogenous fertilizer had significant effects in combination with timothy and rye-grass, but phosphatic and potassic fertilizers had no significant effects on tree growth or crop yield.

Clover and natural sward covers had the least deleterious effect on tree growth and gave the highest yield of fruit. Timothy and rye-grass severely restricted tree growth and crop yield. This was due largely to competition for nitrogen, which was clearly reflected in a reduced nitrogen concentration in the leaves of the trees.

Optimum growth, crop yield and fruit colour in Cox were associated with a nitrogen concentration of 2 . 0-2 . 2% in dry matter of leaf samples taken in August from the mid-third region of extension shoots.

There is evidence from the composition of the leaves of the trees to suggest that clover made available additional nitrogen and phosphate.

There was a positive relationship between the total nitrogen concentration of the tracheal (xylem) sap of shoots at the green-cluster stage and the leaf-nitrogen status in the previous August.

It is suggested that the best method of establishing a permanent cover in orchards, with the least adverse effect on tree growth and nitrogen status, is to sow wild white clover and to allow the slow establishment of indigenous grasses by frequent mowing.     

The Relation Between the Rate of Respiration of an Apple Fruit and its Content of Protein: I. The Value of this Relation Immediately After Picking

Tomato plants of two varieties (Potentate and Immuna) were grown for four seasons with different combinations of magnesium and potassium sulphate in heated glasshouses. Magnesium sulphate was applied either to the soil or as a foliar spray, with untreated plots as controls ; these treatments were combined factorially with two levels of soil potassium. The effects of the treatments on the magnesium and potassium contents of the soil, as extracted by 0 5N-acetic acid, are recorded.

Chlorosis of the leaves was widespread where magnesium was not applied. Foliar spraying effectively controlled the deficiency symptoms; treatment of the soil with magnesium sulphate was only partially successful in the first season but increasingly satisfactory thereafter.

In only one of the four seasons was there a significant increase in yield J due to the correction of magnesium deficiency. In that year (1959) the yields at the higher level of potassium were increased by 15%and 12%by the soil and spray treatments respectively (P=0·001).

The magnesium treatments slightly improved fruit quality as assessed by visual grading, mainly at the very low level of potassium in the last two seasons. The dominant factor affecting fruit quality was potassium, however, which markedly increased the proportion of uniformly coloured fruit and reduced the incidence of ripening disorders.

It is suggested that magnesium deficiency should be controlled by supplying this nutrient rather than by reducing the application of potassium salts below the quantity necessary for high fruit quality.

Variety Immuna gave higher yields and better quality fruit than Potentate throughout the trial.     

The Effects of Nitrogen,Phosphorus, Potassium,Magnesium and Lime in Factorial Combination on the Yields of Glasshouse Tomatoes

Tomato yields and soil analyses from a 3² × 2³ factorial nutritional trial are summarized for six seasons of cropping in heated glasshouse borders. The varieties were Potentate for four seasons, and J168 and Moneymaker (split plot) in the last two seasons. The soil was steamed before planting except in the first and third years.

Deficiencies of nitrogen and phosphorus decreased the yields in five out of six seasons, as also did potassium deficiency in four seasons. Significant positive interactions were found between these three nutrients. The highest level of nitrogen (680–830 lb. N per acre) was favourable when both phosphorus and potassium were at adequate levels in unlimed soil. No yield response was found to potassium in excess of the intermediate level (870 lb. K₂O per acre). The main effect of magnesium was not significant, but a positive phosphorus-magnesium interaction was found for variety Moneymaker.

Lime (carbonate) decreased the yield significantly each season. A significant interaction was found between lime and nitrogen level, the adverse effect of lime occurring at the high and intermediate levels of nitrogen. This effect of lime, and the lime-nitrogen interaction, may be due to induced boron deficiency.     

A comparison of the application of different waste products to a lettuce crop: Effects on plant and soil properties

A romaine-type lettuce (Lactuca sativa L.) was cultivated during three successive crop seasons in an agricultural land near the Wastewater Treatment Plant (WWTP) of Alcázar de San Juan. Four fertilization treatments were compared, including: two different organic fertilizer treatments consisting of (i) air-dried sewage sludge (SS), and (ii) municipal solid waste compost (MSWC), (iii) an inorganic treatment of commercial fertilizer (FER), and (iv) a control treatment in which no fertilizer was applied (CONT). The highest yield was observed in the SS treatment in all crop seasons. In the organic treatment plots there was an increase in macronutrients and organic matter in the soil. An accumulation of heavy metals in the soil was not observed but there was an increase in microbial population in the organic treatment plot, especially in the SS treatment plot. In plant tissue, the continued addition of fertilizers did not produce an accumulative effect of macro- and micronutrients. Low heavy metal content (Cr, Cd, Pb and Hg) was observed in all treatments and crop seasons. Microbiological content was more numerous in the first crop season in SS-treated plants, mainly in lettuce leaves but also in the soil.     

Rubus Stunt: A Virus Disease

In 1958, at three sites in the Vale of Evesham, a progressive increase in the yield of spring cabbage was obtained from increasing rates of application of nitrogenous fertilizers up to 279 lb. N per acre, as Nitrochalk. At a fourth, with later application of fertilizers and a relatively early cutting date, 6 cwt. per acre gave a yield response rather greater than at the other three sites, but higher rates of application of Nitrochalk produced no further increases in yield.

No yield advantage was gained by applying the fertilizer dressing in three doses during the growth of the crop rather than in one dose in the very early spring.

The uptake of potassium, phosphorus, magnesium and calcium by the plants increased as the rate of nitrogenous fertilizer increased. The need to maintain an adequate level of available potassium in the soil when using heavy dressings of nitrogenous fertilizers is emphasized.

The effect of a ploughed-in ley on the recovery of added nitrogen is discussed.     

The Effects of Different Manurial Treatments on The Yield and Mineral Composition of Red Beet

Red beet was grown in factorial manurial experiments at two sites: at Wellesbourne annually from 1954 to 1964 in a rotation of vegetable crops and at Efford in 1959 only.

At Wellesbourne applications of FYM (20 tons per acre per crop), together with NPK fertilizers, consistently gave much higher yields than mineral fertilizers alone, but the relative effect of FYM did not increase as the experiment proceeded.

In the presence of FYM, yields of red beet increased with increasing rates of application of Nitrochalk (up to 124 lb. N per acre), but applications of phosphate and potash fertilizers did not affect yields.

In the absence of FYM, phosphate fertilizers did not increase yields significantly after 1959; there was an important interaction between the effects of the applications of Nitrochalk and SUlphate of potash. Each fertilizer applied alone produced small increases in yield, but when they were applied together at the highest rates used (186 lb. Nand 192 lb. K₂O per acre) large increases in yield were obtained and there was some indication that an even higher rate of application would have given a further increase in yield. At Efford, nitrogenous fertilizers increased yields significantly.

Applications of FYM increased the potassium and decreased the calcium and magnesium contents of red beet leaves and had only small effects on the nitrogen and phosphorus contents; in the roots, only the potassium content was altered (increased) by the FYM applications.

In general, in the absenc~ of FYM only potash fertilizer applications had large, consistent and significant effects on the mineral composition of the leaves and roots. At both sites, applications of sulphate of potash increased the potassium content of the leaves and had a much smaller depressing effect on the calcium and magnesium contents of the leaves but not, in general, of the roots.

The effects of the nitrogenous fertilizers on the total nitrogen content of the roots were relatively small, but could be important in relation to the processing quality of the beet.

The marked differences between the responses of red beet and early potatoes to the manurial treatments are discussed in relation to the nutrient contents of the plants.     

长期施用氮磷钾肥对黄土高原地区苹果产量及土壤养分累积与分布的影响

对连续8 a施用氮磷钾肥的黄土高原地区‘红富士’苹果园的产量及土壤养分变化进行了研究,以探明长期施用氮磷钾化肥对苹果产量与土壤养分累积与分布的影响。结果表明,施用氮磷钾化肥(NPK处理)显著增加了苹果产量,增产率为12.8%～128.3%,增产率随施肥年限增加有增加趋势。NPK处理增加了果园土壤的有效氮、磷、钾含量,其累积量在不同土层中的分布差异较大。与对照(CK)相比较,NPK处理使0～20 cm、20～40 cm和40～60 cm土层中的速效氮含量平均分别增加了24.9 mg·L-1、36.9 mg·L-1和49.7 mg·L-1,速效磷增加了20.1 mg·L-1,12.6 mg·L-1和4.3 mg·L-1,速效钾增加了50.9 mg·L-1、61.8 mg·L-1和31.2 mg·L-1。这表明长期施肥下,果园土壤中速效氮的累积量随着土层深度增加,速效磷的累积量随土层深度减少,速效钾累积主要分布在0～40 cm土层。相关性分析表明,20～40cm土层的速效氮和速效磷含量与当年的苹果产量呈显著正相关关系,土壤速效养分含量与上一年度苹果产量的相关性较差。     

不同栽培处理方式对早春辣椒产量的影响

通过不同播期、密度、施肥水平及覆膜处理,比较辣椒的前期产量及总产量。结果表明,辣椒栽培全程覆膜,播期为10月5日,株行距为35cm×50cm,每1hm2施750kg复合肥、375kg磷肥、150kg钾肥及7500kg有机肥时,早春辣椒前期产量和总产量均最高,且栽培全程覆膜对早春辣椒产量具有极显著效应。     

A Note on the Growth-Regulating Activity of 2:6-Dichlorophenoxyacetic Acid

During each of the four years 1957-60 the growth of the carrot crops in a long-term manurial experiment was studied. Significant increases in the yield of roots were produced by the application of farmyard manure and of potassic fertilizer but not by the application of nitrogenous or phosphatic fertilizers. The mean annual yields, and the responses to the applications of FYM and K, varied considerably from year to year.

The applications of FYM resulted in increases of 15-20% in the net assimilation rates and relative growth rates of the plants but these increases persisted for only 4-7 weeks when growth of the leaves on all plots was exponential. Subsequently net assimilation and relative growth rates of the plants on the FYM plots were slightly less than those on the no-FYM plots. It appeared that the initial differences in net assimilation rates were the main cause of the increased leafiness of the plants on the FYM plots, and hence of the increases in yields of roots.

Year-to-year differences in the total weight of leaves produced were related mainly to differences in the amount of rainfall during their growth. Yearly variation in root yields, however, was related both to the amount and to the distribution of the rainfall during growth.

The relative importance of variations in net assimilation rate and in leaf weight ratio are discussed.     

Seasonal Trends in Mineral Nitrogen Content of the Soil in a Long-Term Npk Trial on Dessert Apples

The seasonal levels of ammonium and nitrate nitrogen were determined, over 3 years, within the top 24 inches of soil of a long-term NPK trial on dessert apples. The four treatments selected provided comparisons of cultivated and grassed plots receiving spring applications of Nitrochalk with those having received no nitrogen since 1930. The three seasons included a very dry one in 1959 and the unusually wet summer of 1960.

Ammonium nitrogen did not persist as such for long periods, and nitrate nitrogen was the major form of mineral nitrogen.

There was a marked contrast between the levels under the two management systems. Grass maintained a low level throughout most of the season, whereas a steady rise in nitrate nitrogen took place until July or later in the cultivated soil; thereafter, the level fell in response to rainfall. By mid-winter, very little nitrate nitrogen remained in the 24-inch profile.

Applications of nitrogenous fertilizer did not markedly affect the mineral nitrogen status in the grassed plots but, in the cultivated soil, levels substantially exceeding the annual applications were found. These seasonal trends are discussed in relation to the processes involved in the cycling of mineral nitrogen.

Estimates of the annual amounts mineralized in the cultivated soil receiving no added nitrogen suggest that even after 30 years this amount may be of the same order as the net uptake by the trees, thus explaining their apparently satisfactory nitrogen status.

In the grassed plots, the rapid re-cycling of nitrogen from the clippings may be an important factor in maintaining an adequate supply to the tree.     

氮磷钾肥对莲藕产量和品质的影响

通过分别施用不同水平的氮磷钾肥,研究其对莲藕(Nelumbo nucifera Gaertn.)产量和品质的影响.研究结果表明,施用氮磷钾肥对莲藕的产量和品质有明显的影响,施肥的增产效应为氮肥略高于钾肥,氮肥和钾肥远高于磷肥;不同水平的氮磷钾用量中,中等施肥量的处理N450、P180和K450的莲藕产量最高;合理施用氮...     

盐渍化土壤枸杞叶养分变化规律研究

通过311-A拟饱和最优回归试验,研究了盐渍化土壤枸杞园不同氮磷钾配比、不同生育期、枸杞叶片养分含量变化规律。结果表明:较优的氮磷钾配比,叶片养分含量随着施肥量的增加而增大;2 a间叶片全氮含量在全生育期均呈"M"型变化趋势,全磷变化不大,基本趋于平缓,全钾在现蕾初期含量较高,到秋果后期含量逐渐降低;中度盐渍化土壤叶片养分变化与轻度及非盐渍化土壤叶片养分有较大差异。     

不同减肥增效模式对生菜产量和品质的影响

为阐明不同减肥增效模式下土壤和作物各指标的变化规律,采用田间小区试验研究了不同减肥措施对生菜产量、品质及土壤理化性质变化的影响.试验结果表明,不同化肥减量措施中,推荐施肥的生菜产量最高,为2907 kg/667 m2.减肥增效措施下,生菜产量比习惯施肥增加19.83％～76.82％,叶片硝酸含量降低47.49％～63....     

Effect of organic and inorganic fertilizers applied during successive crop seasons on growth and nitrate accumulation in lettuce

A romaine-type lettuce (Lactuca sativa L.) cv. Corsica was cultivated during three successive crop seasons (late-spring, late-autumn and late-winter) in the same soil of an experimental greenhouse in S.W. Peloponnese, Greece. Seven long-term fertilization treatments were tested for their effect on plant growth and nitrate concentration in the external lettuce leaves. Treatments included: three different doses of organic fertilization (composted sheep manure) applied at the start of each crop season, three different doses of inorganic N fertilization applied via fertigation during each crop season, and a control treatment in which no fertilizer was applied. A drip irrigation system was used to water all plants. The highest nitrate levels were observed in the medium and maximum inorganic fertilization treatments (572–664 mg kg⁻¹) in all crop seasons. They were significantly higher compared to the respective organic fertilization treatments (253–435 mg kg⁻¹) and all other fertilization treatments (148–435 mg kg⁻¹). Crop season affected lettuce growth more than nitrate accumulation in the lettuce leaves: lettuce biomass production was the smallest and most uniform in the late-autumn season and did not respond to the fertilization treatments tested (ranging from 409 to 439 g plant⁻¹), while in the late-spring season biomass production was the highest and most variable (561–841 g plant⁻¹), it correlated with nitrate concentration in the leaves and in the medium and maximum inorganic fertilizer doses it significantly exceeded production from all other fertilization treatments (827–841 g plant⁻¹). Following the three crop seasons the residual availability of N, P and K was clearly enhanced in the soil receiving the organic compared to the inorganic fertilization. Nitrate concentration in lettuce leaves was far below the upper limits set by the European Commission in all fertilization treatments throughout the three crop seasons, a result attributed mainly to the sufficient level of light intensity and duration throughout the year in Southern Greece.     

The Effects of Different Manurial Treatments on The Yield and Mineral Composition of Early Potatoes

The effects of different manurial treatments on the yield and mineral composition of early potatoes are described. The crops were grown annually from 1954 to 1964 in a rotation of vegetable crops in a factorial manurial experiment on a sandy loam at Wellesbourne and, in i960 only, on a very fine sandy loam at Efford.

At Wellesbourne, farmyard manure (20 tons per acre per crop) with fertilizers consistently produced much higher yields than mineral fertilizers alone, and the relative effect of FYM increased from 1954 to 1959 but not subsequently. In years when moisture supplies were adequate, the larger part of the increase in yield could be attributed to effects of FYM on the early growth of the plants, and a smaller part to the increased rate of bulking of the tubers on the FYM plots. In dry years, however, growth during the harvest period was much slower on the fertilizer plots than on the FYM plots and the additional relative increase in yield on the latter during this period caused the overall effect of FYM to be larger than in the wetter years.

In the absence of FYM, each of the major nutrients N, P and K gave significant yield increases, but the need for adequate applications of phosphate and potash fertilizers together was emphasized by a marked interaction between their effects on yield. Applications of phosphate fertilizers had a particularly important effect early in the bulking period, whereas the effects of the nitrogenous fertilizers were greater at the later stages. In the presence of FYM, the fertilizer applications had significant effects only at the later stages of bulking, but at this time the amounts needed to give maximum yields were similar to those needed in the absence of FYM (124 lb. N, 36 lb. P₂O₅ 144 lb. K₂O (estimated), each per acre).

At Efford, applications of up to 4 cwt. per acre of sulphate of ammonia and 2 cwt. per acre of superphosphate (18% P₂2O₅) gave significant increases in yield, and higher rates would probably have given still higher yields. Potash fertilizers did not affect yields although they markedly increased the potash contents of the plants. The differences between the responses at the two sites are discussed in relation to soil conditions.

The leaves of plants manured with FYM (Wellesbourne) contained much more potassium and slightly more phosphorus than leaves from unmanured plants and, while the differences in potassium content were larger towards the end of the bulking period than at the beginning, the reverse was true of the phosphorus contents. Thus, to use leaf composition data to indicate possible shortages of nutrients in the soil, the samples of leaves for chemical analysis must be taken at several different times during the growth of the crop. The value, if any, of extra nutrients for FYM-manured plants cannot at present be assessed.

At Efford, applications of sulphate of potash increased the potassium content of the leaves to levels approaching those found in the manured plants at Wellesbourne and higher than those in the unmanured plants. Because of marked interactions between the effects of the phosphate and potash fertilizers at Wellesbourne and indications that phosphate applications at Efford may have been too low to ensure maximum yields, it does not seem possible to combine the data from the two experiments in order to suggest levels of the major nutrients in the potato leaves, at any particular stage or stages, which may be considered adequate for maximal yield production.

At Wellesbourne the standard error per plot was smaller for the manured series (8·1%) than for the unmanured (12·9%), indicating that growth was more uniform on the former.     

Long-term studies on yield,quality and soil fertility of lemongrass (Cymbopogon fiexuosus) in relation to nitrogen application

Summary

A field experiment was conducted over five years (1992–97) at Bangalore (13.58N, 77.558E, 930.m above mean sea level) to study the effect of nitrogen application (0, 50, 100 and 150.kg N ha^–1 year^–1) on yield, oil quality and soil fertility of lemongrass (Cymbopogon fiexuosus) in the semi-arid tropical conditions of South India. Fresh herbage yield of lemongrass differed significantly between years; the yields increased up to the second year after which they started to decline. During the five years, the response to nitrogen was linear, while still maintaining the same content and quality of essential oil. The oil content and chemical composition of oil did not change as the crop aged. Application of nitrogen and phosphorus maintained the fertility of the soil while potassium depletion was noticed.     

The Effect of Different Irrigation Treatments on the Growth and Yield of Early Summer Cauliflowers

Lettuce were grown during the winter of 1957–58 on the plots of a long-term manurial experiment in which the treatments had been applied to each crop from 1954 to 1957. Three rates of each of the three nutrients N, P and K were applied either with or without farmyard manure (20 tons per acre per crop) in a 3³ × 2 factorial design.

The mean yield from the plots which received farmyard manure (FYM) together with fertilizers was more than twice that from the plots which received fertilizers alone; the extra yield came from the greater number of lettuces that reached marketable condition on the former plots and not from an increase in the size of the plants. The date by which 50% of the plants that eventually reached marketable condition had been cut was almost 8 days earlier for the FYM plots than for the no-FYM plots. The different rates and combinations of fertilizers, when applied with FYM, did not produce different yield effects.

In the absence of FYM, applications of sulphate of potash and superphosphate each increased yields significantly (P =.0·05); applications of Nitrochalk, however, reduced yields but the reduction just failed to reach significance (P = 0·05). The treatments did not affect the 50% cutting date.

Where FYM had been applied, the fertilizer applications did not have differential effects on the mineral composition of the lettuce plants but, on average, there was twice as much potassium in the dry matter of plants (7·8%) as in plants from the no-FYM plus fertilizer plots (3·9%). In the absence of FYM, the fertilizer applications had marked differential effects on the mineral composition of the plants and these effects are discussed in relation to yield.     

A Long-Term Manurial Trial on Dessert Apple Trees

A factorial NPK fertilizer trial was started in 1931 with newly planted dessert apple trees. Two varieties (Cox’s Orange Pippin and Beauty of Bath) and four rootstocks (M.I, M.V, M.IX and M.XII) were represented. By 1953. after the orchard was thinned in two stages, only one experimental tree, of Cox’s Orange Pippin on M.XII, remained in each plot; at this time a fourth factor was added by establishing a sward (S) in half the plots and continuing to cultivate the remainder during each spring and summer.

Severe deficiency symptoms developed early in the trial on plots receiving no potash. Recovery followed the overall annual application from 1937 of 2 cwt. per acre sulphate of potash, additional to the treatment comparison of nil v. 2 cwt. per acre, but large differences in tree size and cropping persisted. These differences were not greatest with the variety or the rootstock showing the most severe leaf scorch symptoms.

The overall potash application was discontinued in 1953, but the levels of “ available” potassium in the soil had by then been raised, and the trees of Cox on M.XII did not develop potassium deficiency over the next ten years. On the contrary, there was evidence that the higher level was now harmful, perhaps because of induced incipient magnesium deficiency.

Superphosphate (18% P₂O₅, 5 cwt. per acre per annum) did not affect the performance of the trees and only slightly increased the phosphorus concentration in the leaves. Much greater increases in leaf phosphorus were brought about by grassing down, particularly in the absence of nitrogen applications.

In the nitrogen treatment sulphate of ammonia was applied initially at 1½ cwt. per acre per annum, but this rate was increased to 3 cwt. per acre in 1941 and then to 6 cwt. per acre in 1953 ; from 1958 Nitrochalk at an equivalent rate was applied instead of sulphate of ammonia. This nitrogen treatment increased the total crop per plot over the first I7 years by 15%, and the total crop of the Cox on M.XII over the period 1953-62 by 25*#x0025;. The response was especi~lly marked in the last few years when the trees with and without nitrogen were still virtually indistinguishable in leaf colour ; values for nitrogen concentration on a dry-weight basis in mid-shoot leaves for August 1962 were 2·9% and 2·8% respectively.

Trees receiving nitrogen were grassed down in 1953 without reduction in total crop over the next ten years, though nitrogen status was depressed in the first few seasons. This depression was much more severe and persistent with the trees not receiving nitrogen, despite the abundance of clover in the swards on those plots.

The advantages of grassing down on fruit quality may be largely due to the restriction of nitrogen supply to the tree.     

Influence of nitrogen form,growing season and sulfur fertilization on yield and the content of nitrate and vitamin C of broccoli

The objective of this study was to determine the effects of nitrogen (N) sources, sulfur (S) and growing seasons on yield and the content of nitrate and vitamin C of broccoli (Brassica oleracea L. spp. Italica). Three N fertilizers (ammonium sulfate, ammonium nitrate and urea) were side-dressed while two levels of sulfur (0.0 and 0.5%) were sprayed on broccoli plants grown in both spring and fall-winter seasons. Here, we report on the interaction between N-source and S supply, yield, and nitrate content and discuss the relevance of this interaction in relation to crop-management strategies under different growing seasons. In the fall-winter season, broccoli yield of “Sultan F1”, “Majestic F1” and “Marathon F1” were 21.23%, 128.52% and 88.53% higher than spring season. Furthermore, S application increased the yield by 9% average over growing seasons, cultivars and N-forms. Also, application of urea as N-source decreased the yield by approximately 13–15% than other N-sources. High curd nitrate accumulation was attributed with spring season and “Marathon F1”, however, less accumulation was found in fall-winter season and “Majestic F1”. Fertilizers containing N forms that not ready available to the crop, i.e. ammonium sulfate and urea, decreased nitrate than fast N-release fertilizer (ammonium nitrate), but their effect on the yield was different. Highest yield with low content of nitrate was achieved when ammonium sulfate combined with sulfur were used during fall-winter season, especially in cv. “Marathon F1”. N-source and sulfur application had no effect on vitamin C, conversely, it was affected by growing season and tested genotypes. Therefore, additions of ammonium sulfate and sulfur application in the field of broccoli were essential to produce higher yield with good quality curds that pose minimum health risk to human.